A search for new physics in events with two highly Lorentz-boosted Z bosons and large missing transverse momentum is presented. The analyzed proton-proton collision data, corresponding to an integrated luminosity of 137 fb$^{-1}$, were recorded at $\sqrt{s} =$ 13 TeV by the CMS experiment at the CERN LHC. The search utilizes the substructure of jets with large radius to identify quark pairs from Z boson decays. Backgrounds from standard model processes are suppressed by requirements on the jet mass and the missing transverse momentum. No significant excess in the event yield is observed beyond the number of background events expected from the standard model. For a simplified supersymmetric model in which the Z bosons arise from the decay of gluinos, an exclusion limit of 1920 GeV on the gluino mass is set at 95% confidence level. This is the first search for beyond-standard-model production of pairs of boosted Z bosons plus large missing transverse momentum.
A review of the status of searches for Supersymmetry at the Tevatron Collider as of the Summer of 1997. This is a new version of the previous review, substantially shortened to fit editorial guidelines, and significantly different to warrant a separate posting. To appear in "Perspectives on Supersymmetry", ed. G.L. Kane (World Scientific, Singapore).
This paper reviews some of the most recent results from CDF and D0 experiments on searches for supersymmetry (SUSY) at the Tevatron. We focus on searches for chargino/neutralino, stop, sbottom, and long lived massive SUSY particles, on data samples up to ~1 fb-1. No signal was observed, and constraints are set on the SUSY parameter space.
The D0 and CDF experiments at the proton-antiproton collider Tevatron have extensively searched for the Higgs boson and signals of supersymmetry using a wide range of signatures. The status of these searches is reviewed with a focus on recent measurements.
These lectures contain an introduction to the search for supersymmetry at hadron colliders. The Tevatron is one of high-energy physics most sophisticated tools. The high center-of-mass energy of its proton-antiproton collisions makes it an ideal place to search for physics beyond the Standard Model, such as supersymmetry. Two experiments, CDF and DØ, completed a long data taking period in summer of 1995, yielding over $100 p b^{-1}$ of proton-- antiproton interactions. The data recorded by the experiments are still being analysed. The lectures outline the strategies in the search for supersymm…
A search for supersymmetry in the context of general gauge-mediated (GGM) breaking with the lightest neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest is presented. The data sample corresponds to an integrated luminosity of 36 inverse picobarns recorded by the CMS experiment at the LHC. The search is performed using events containing two or more isolated photons, at least one hadronic jet, and significant missing transverse energy. No excess of events at high missing transverse energy is observed. Upper limits on the signal cross section for GGM super…
CDF and D0 collaborations analyzed up to 200 pb-1 of the delivered data in search for different supersymmetry signatures, so far with negative results. We present results on searches for chargino and neutralino associated production, squarks and gluinos, sbottom quarks, gauge mediated SUSY breaking and long lived heavy particles.
We present the results of searches for Supersymmetry in various topologies that lead to final states with jets and missing transverse momentum together with one or more isolated leptons, one or two photons or a photon and a lepton. The searches are performed using data collected by the CMS experiment at the LHC in pp-collisions at a center-of-mass energy of 7 TeV. Various data- driven techniques used to measure the Standard Model backgrounds are discussed. The results are interpreted in the CMSSM framework.
The production of chargino-neutralino pairs and their subsequent leptonic decays is one of the most promising supersymmetry (SUSY) signatures at the Tevatron $p\bar{p}$ collider. We present here the most recent results on the search for the three-lepton and missing-transverse-energy SUSY signature using data collected with the CDF II detector. The results are interpreted within the minimal supergravity (mSugra) scenario.
We report results of a search for supersymmetry (SUSY) with gauge-mediated symmetry breaking in di-photon events collected by the D0 experiment at the Fermilab Tevatron Collider in 2002--2006. In 1.1 fb$^{-1}$ of data, we find no significant excess beyond the background expected from the standard model and set the most stringent lower limits to date for a standard benchmark model on the lightest neutralino and chargino masses of 125 GeV and 229 GeV, respectively, at 95% confidence.
A search for supersymmetry is presented using a sample of events with b jets and missing transverse momentum. The search uses a data sample of proton-proton collisions at a centre-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 35 inverse picobarns, collected with the CMS detector. A total of 0.33 +0.43 -0.33 (stat.) +/- 0.13 (syst.) events is predicted, using control samples in the data, to arise from standard model processes, and one event is observed in the data. Upper limits are set at the 95% confidence level on the cross sections of benchmark supersymmetric models.
Results are reported for a search for supersymmetry in final states with photons and missing transverse momentum in proton-proton collisions at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ collected at a center-of-mass energy of 13 TeV using the CMS detector. The results are interpreted in the context of models of gauge-mediated supersymmetry breaking. Production cross section limits are set on gluino and squark pair production in this framework. Gluino masses below 1.86 TeV and squark masses below 1.59 TeV are excluded at 95% confidence level.
A search for production of supersymmetric particles in final states containing jets, missing transverse momentum, and at least one hadronically decaying tau lepton is presented. The data were recorded by the ATLAS experiment in sqrt(s) = 7 TeV proton-proton collisions at the Large Hadron Collider. No excess above the Standard Model background expectation was observed in 2.05 fb-1 of data. The results are interpreted in the context of gauge mediated supersymmetry breaking models with Mmess = 250 TeV, N5 = 3, mu > 0, and Cgrav = 1. The production of supersymmetric particles is excluded at 95% C.…
We present the results of a search for anomalous production of diphoton events with large missing transverse energy using the Collider Detector at Fermilab. In 202 $\invpb$ of $\ppbar$ collisions at $\sqrt{s}=1.96$ TeV we observe no candidate events, with an expected standard model background of $0.27\pm0.07({\rm stat})\pm0.10({\rm syst})$ events. The results exclude a lightest chargino of mass less than 167 GeV/$c^2$, and lightest neutralino of mass less than 93 GeV/$c^2$ at 95% C.L. in a gauge--mediated supersymmetry-- breaking model with a light gravitino.
We present a search for Physics beyond the Standard Model (SM) in final states with a Z boson, jets and missing transverse energy, using a data sample collected in 2011 by the CMS detector at the Large Hadron Collider corresponding to an integrated luminosity of 2.1 /fb. This final state is predicted in several models of Physics beyond the SM, including supersymmetry. A novel analysis method is exploited, the Jet-Z Balance method, and a precise determination of the total SM background is obtained using a control sample from data. In the absence of any significant excess beyond the SM backgroun…
In this paper, a search for supersymmetry (SUSY) is presented in events with two opposite-sign isolated leptons in the final state, accompanied by hadronic jets and missing transverse energy. An artificial neural network is employed to discriminate possible SUSY signals from a standard model background. The analysis uses a data sample collected with the CMS detector during the 2011 LHC run, corresponding to an integrated luminosity of 4.98 inverse femtobarns of proton-proton collisions at the center-of-mass energy of 7 TeV. Compared to other CMS analyses, this one uses relaxed criteria on miss…
We present the results of a search for supersymmetry with gauge-mediated breaking and $\NONE\toγ\Gravitino$ in the $γγ$+missing transverse energy final state. In 2.6$\pm$0.2 \invfb of $p{\bar p}$ collisions at $\sqrt{s}$$=$1.96 TeV recorded by the CDF II detector we observe no candidate events, consistent with a standard model background expectation of 1.4$\pm$0.4 events. We set limits on the cross section at the 95% C.L. and place the world's best limit of 149\gevc on the \none mass at $τ_{\tildeχ_1^0}$$<<$1 ns. We also exclude regions in the \none\ mass-lifetime plane for $τ_{\tildeχ_1^0}$$\…
A search for gaugino pair production with a trilepton signature in the framework of R-parity violating supersymmetry via the couplings lambda_121, lambda_122, or lambda_133 is presented. The data, corresponding to an integrated luminosity of L~360/pb, were collected from April 2002 to August 2004 with the D0 detector at the Fermilab Tevatron Collider, at a center-of-mass energy of sqrt(s)=1.96 TeV. This analysis considers final states with three charged leptons with the flavor combinations eel, mumul, and eetau (l=e or mu). No evidence for supersymmetry is found and limits at the 95% confidenc…
The results of a search for new physics in final states with photons and missing transverse energy are reported. The study is based on a sample of proton-proton collisions collected at a center-of-mass energy of 13 TeV with the CMS detector in 2015, corresponding to an integrated luminosity of 2.3 inverse femtobarns. Final states with two photons and significant missing transverse energy are used to search for supersymmetric particles in models of supersymmetry (SUSY) with general gauge-mediated (GGM) supersymmetry breaking. No excess is observed with respect to the standard model expectation,…
We use the three lepton and missing energy "trilepton" signature to search for chargino-neutralino production with 2.0 inverse femtobarns of integrated luminosity collected by the CDF II experiment at the Tevatron ppbar collider. We expect an excess of approximately 11 supersymmetric events for a choice of parameters of the mSUGRA model, but our observation of 7 events is consistent with the standard model expectation of 6.4 events. We constrain the mSUGRA model of supersymmetry and rule out chargino masses up to 145 GeV/c^2 for a specific choice of parameters.
This Letter presents the first search for supersymmetry in final states containing one isolated electron or muon, jets, and missing transverse momentum from sqrt{s} = 7 TeV proton-proton collisions at the LHC. The data were recorded by the ATLAS experiment during 2010 and correspond to a total integrated luminosity of 35 pb-1. No excess above the standard model background expectation is observed. Limits are set on the parameters of the minimal supergravity framework, extending previous limits. For A_0 = 0 GeV, tan beta = 3, mu > 0 and for equal squark and gluino masses, gluino masses below 700…
A search for supersymmetry involving events with at least one photon, one electron or muon, and large missing transverse momentum has been performed by the CMS experiment. The data sample corresponds to an integrated luminosity of 19.7 inverse femtobarns of pp collisions at sqrt(s) = 8 TeV, produced at the CERN LHC. No excess of events is observed beyond expectations from standard model processes. The result of the search is interpreted in the context of a general model of gauge-mediated supersymmetry breaking, where the charged and neutral winos are the next-to-lightest supersymmetric particl…
Both Tevatron experiments, D0 and CDF, have searched for signs of Supersymmetry in the present Run II data sample, using integrated luminosities of up to 260/pb collected in ppbar collisions at a center-of-mass energy of 1.96TeV. In these proceedings, new results are presented in the search for squarks and gluinos in the jets and missing transverse energy final state, associated production of charginos and neutralinos with multilepton final states, search for the rare decay B_s->mumu, searches allowing R-parity violation (muons+jets, multileptons), and searches in the gauge mediated supersymme…
We present an update of a search for supersymmetry in final states containing jets, missing transverse momentum, and one isolated electron or muon, using 1.04 fb^-1 of proton-proton collision data at sqrt{s} = 7 TeV recorded by the ATLAS experiment at the LHC in the first half of 2011. The analysis is carried out in four distinct signal regions with either three or four jets and variations on the (missing) transverse momentum cuts, resulting in optimized limits for various supersymmetry models. No excess above the standard model background expectation is observed. Limits are set on the visible…
The results of a search for supersymmetry in events with large missing transverse momentum and heavy flavour jets using an integrated luminosity corresponding to 2.05 fb^-1 of pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the Large Hadron Collider are reported. No significant excess is observed with respect to the prediction for Standard Model processes. Results are interpreted in a variety of R-parity conserving models in which scalar bottoms and tops are the only scalar quarks to appear in the gluino decay cascade, and in an SO(10) model framework. Gluino masses up to …
With almost 0.5fb-1 of ppbar-collisions delivered in Tevatron Run II, both experiments CDF and D0 are reporting first results from a vast number of search analyses. This article summarizes the current status of Tevatron searches for Higgs bosons within the Standard Model and its extensions as well as direct searches for supersymmetric particles. Signatures for production of squarks, gluinos, charginos and neutralinos as predicted by gravity- and gauge-mediated SUSY breaking scenarios have been considered. No evidence for Higgs bosons or SUSY particles has been found so far. New limits are deri…
We discuss a search for natural Supersymmetry in events with at least one bottom-quark jet using razor variables in proton-proton collisions at 8 TeV with the CMS detector. The event distribution in the plane defined by the razor variables $R^2$ and $M_R$ is studied, searching for a peaking signal on top of a smoothly falling standard model background. The data are consistent with the expected background, modeled by a template function. The 95% C.L. exclusion limit on the masses of the gluino and lightest supersymmetric particle in a benchmark simplified model is presented. For a lightest supe…
Results are reported from a search for physics beyond the standard model in proton-proton collisions at a center-of-mass energy of 7 TeV, focusing on the signature with a single, isolated, high-transverse-momentum lepton (electron or muon), energetic jets, and large missing transverse momentum. The data sample comprises an integrated luminosity of 36 inverse picobarns, recorded by the CMS experiment at the LHC. The search is motivated by models of new physics, including supersymmetry. The observed event yields are consistent with standard model backgrounds predicted using control samples obtai…
A search for events with jets and missing transverse energy is performed in a data sample of pp collisions collected at sqrt(s) = 7 TeV by the CMS experiment at the LHC. The analyzed data sample corresponds to an integrated luminosity of 1.14 inverse femtobarns. In this search, a kinematic variable, alphaT, is used as the main discriminator between events with genuine and misreconstructed missing transverse energy. No excess of events over the standard model expectation is found. Exclusion limits in the parameter space of the constrained minimal supersymmetric extension of the standard model a…
We present the results of a search for supersymmetry with gauge-mediated breaking and $\NONE\toγ\Gravitino$ in the $γγ$+missing transverse energy final state. In 2.6$\pm$0.2 \invfb of $p{\bar p}$ collisions at $\sqrt{s}$$=$1.96 TeV recorded by the CDF II detector we observe no candidate events, consistent with a standard model background expectation of 1.4$\pm$0.4 events. We set limits on the cross section at the 95% C.L. and place the world's best limit of 149 \gevc on the \none mass at $τ_{\tildeχ_1^0}$$\ll$1 ns. We also exclude regions in the \none\ mass-lifetime plane for $τ_{\tildeχ_1^0}$…
Results are presented of a search for supersymmetric particles in events with large missing transverse momentum and at least one heavy flavour jet candidate in sqrt{s} = 7 TeV proton-proton collisions. In a data sample corresponding to an integrated luminosity of 35 pb-1 recorded by the ATLAS experiment at the Large Hadron Collider, no significant excess is observed with respect to the prediction for Standard Model processes. For R-parity conserving models in which sbottoms (stops) are the only squarks to appear in the gluino decay cascade, gluino masses below 590 GeV (520 GeV) are excluded at…
A search for supersymmetry in final states with jets and missing transverse energy is performed in pp collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The data sample corresponds to an integrated luminosity of 4.98 inverse femtobarns collected by the CMS experiment at the LHC. In this search, a dimensionless kinematic variable, alphaT, is used as the main discriminator between events with genuine and misreconstructed missing transverse energy. The search is performed in a signal region that is binned in the scalar sum of the transverse energy of jets and the number of jets identified …
We present the searches for supersymmetry (SUSY) in two channels, two photons plus missing transverse energy and a photon plus a lepton plus missing transverse energy with the CMS detector using approximately 36 $\rm{pb}^{-1}$ of pp collision at 7 TeV. No excess of events above the standard model predictions is found. Limits are set for the squark, gluino and wino masses in the general gauge-mediated SUSY context.
The results of a search for new physics in final states with jets, either photons or leptons, and low missing transverse momentum are reported. The study is based on a sample of proton-proton collisions collected at center-of-mass energy sqrt(s) = 8 TeV with the CMS detector in 2012. The integrated luminosity of the sample is 19.7 inverse femtobarns. Many models of new physics predict the production of events with jets, electroweak gauge bosons, and little or no missing transverse momentum. Examples include stealth models of supersymmetry (SUSY), which predict a hidden sector at the electrowea…
Searches for supersymmetric particles in channels with one or more photons and missing energy have been performed with data collected by the ALEPH detector at LEP. The data consist of 11.1 pb-1 at $\sqrt{s} = 161 GeV$, 1.1 pb-1 at 170 GeV and 9.5 pb-1 at 172 GeV. The e+e- -> nunu+photon cross section is measured. The data are in good agreement with predictions based on the Standard Model, and are used to set upper limits on the cross sections for anomalous photon production. These limits are compared to two different SUSY models and used to set limits on the neutralino mass. A limit of 71 GeV/…
A search for supersymmetry in events with four or more charged leptons (electrons, muons and $τ$-leptons) is presented. The analysis uses a data sample corresponding to $139\,\mbox{fb\(^{-1}\)}$ of proton-proton collisions delivered by the Large Hadron Collider at $\sqrt{s}=13$ TeV and recorded by the ATLAS detector. Four-lepton signal regions with up to two hadronically decaying $τ$-leptons are designed to target several supersymmetric models, while a general five-lepton signal region targets any new physics phenomena leading to a final state with five charged leptons. Data yields are consist…
Results from a search for supersymmetry in events with four or more charged leptons (electrons, muons and taus) are presented. The analysis uses a data sample corresponding to 36.1 fb$^{-1}$ of proton-proton collisions delivered by the Large Hadron Collider at $\sqrt{s}=13$ TeV and recorded by the ATLAS detector. Four-lepton signal regions with up to two hadronically decaying taus are designed to target a range of supersymmetric scenarios that can be either enriched in or depleted of events involving the production and decay of a $Z$ boson. Data yields are consistent with Standard Model expect…
A search for supersymmetry with R-parity conservation in proton-proton collisions at a centre-of-mass energy of 7 TeV is presented. The data correspond to an integrated luminosity of 35 inverse picobarns collected by the CMS experiment at the LHC. The search is performed in events with jets and significant missing transverse energy, characteristic of the decays of heavy, pair-produced squarks and gluinos. The primary background, from standard model multijet production, is reduced by several orders of magnitude to a negligible level by the application of a set of robust kinematic requirements. …
A search motivated by supersymmetric models with light top squarks is presented using proton-proton collision data recorded with the CMS detector at a center-of-mass energy of sqrt(s) = 7 TeV during 2011, corresponding to an integrated luminosity of 4.98 inverse femtobarns. The analysis is based on final states with a single lepton, b-quark jets, and missing transverse energy. Standard model yields are predicted from data using two different approaches. The observed event numbers are found to be compatible with these predictions. Results are interpreted in the context of the constrained minima…
Many models of new physics, including versions of supersymmetry (SUSY), predict production of events with low missing transverse energy, electroweak gauge bosons, and many energetic final-state particles. The stealth SUSY model yields this signature while conserving R-parity by means of a new hidden sector in which SUSY is approximately conserved. The results of a general search for new physics, with no requirement on missing transverse energy, in events with two photons and four or more hadronic jets are reported. The study is based on a sample of proton-proton collisions at sqrt(s) = 7 TeV c…
Results are presented from a search for physics beyond the standard model based on events with large missing transverse energy, at least three jets, and at least one, two, or three b-quark jets. The study is performed using a sample of proton-proton collision data collected at sqrt(s) = 7 TeV with the CMS detector at the LHC in 2011. The integrated luminosity of the sample is 4.98 inverse femtobarns. The observed number of events is found to be consistent with the standard model expectation, which is evaluated using control samples in the data. The results are used to constrain cross sections …
We review the status of searches for Supersymmetry at the Tevatron Collider. After discussing the theoretical aspects relevant to the production and decay of supersymmetric particles at the Tevatron, we present the current results for Runs Ia and Ib as of the summer of 1997. To appear in the book "Perspectives in Supersymmetry", edited by G.L. Kane, World Scientific.
We present a search for like-sign dielectron plus multijet events using 107 pb-1 of data in \ppbar collisions at $\sqrt{s} = 1.8$ TeV collected in 1992-95 by the CDF experiment. Finding no events that pass our selection, we set $σ\cdot Br$ limits on two SUSY processes that can produce this experimental signature: gluino-gluino or squark-antisquark production with R-parity violating decays of the charm squark or lightest neutralino via a non-zero lambda'_121 coupling. We compare our results to NLO calculations for gluino and squark production cross sections and set lower limits on M(gluino), M(…
A search for supersymmetry (SUSY) in events with large missing transverse momentum, jets, and at least one hadronically decaying tau lepton, with zero or one additional light lepton (e/mu), has been performed using 4.7 fb-1 of proton-proton collision data at sqrt(s) = 7 TeV recorded with the ATLAS detector at the Large Hadron Collider. No excess above the Standard Model background expectation is observed and a 95% confidence level visible cross-section upper limit for new phenomena is set. In the framework of gauge-mediated SUSY-breaking models, lower limits on the mass scale Lambda are set at…
In models of anomaly-mediated supersymmetry breaking (AMSB), the lightest chargino is predicted to have a lifetime long enough to be detected in collider experiments. This letter explores AMSB scenarios in pp collisions at sqrt(s) = 7 TeV by attempting to identify decaying charginos which result in tracks that appear to have few associated hits in the outer region of the tracking system. The search was based on data corresponding to an integrated luminosity of 1.02 fb^-1 collected with the ATLAS detector in 2011. The pT spectrum of candidate tracks is found to be consistent with the expectatio…
A search is presented for photonic signatures motivated by generalised models of gauge-mediated supersymmetry breaking. This search makes use of $20.3{\rm fb}^{-1}$ of proton-proton collision data at $\sqrt{s}=8$ TeV recorded by the ATLAS detector at the LHC, and explores models dominated by both strong and electroweak production of supersymmetric partner states. Four experimental signatures incorporating an isolated photon and significant missing transverse momentum are explored. These signatures include events with an additional photon, lepton, $b$-quark jet, or jet activity not associated w…
A search is presented for photonic signatures, motivated by generalized models of gauge-mediated supersymmetry breaking. This search makes use of proton-proton collision data at $\sqrt{s}$ = 13 TeV corresponding to an integrated luminosity of 36.1 fb$^{-1}$ recorded by the ATLAS detector at the LHC, and it explores models dominated by both strong and electroweak production of supersymmetric partner states. Experimental signatures incorporating an isolated photon and significant missing transverse momentum are explored. These signatures include events with an additional photon or additional jet…
Results of a search for supersymmetry are presented using events with a photon, an electron or muon, and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 35.9 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} =$ 13 TeV, produced by the LHC and collected with the CMS detector in 2016. Theoretical models with gauge-mediated supersymmetry breaking predict events with photons in the final state, as well as electroweak gauge bosons decaying to leptons. Searches for events with a photon, a lepton, and missing transverse momentum …
The sensitivity for CMS searches for supersymmetry is evaluated in the context of an upgraded LHC at a center-of-mass energy of 14 TeV and an integrated luminosity of 300 fb-1. Results for several key searches for supersymmetry are presented including direct and gluino-mediated stop and sbottom production and electroweak production of supersymmetric particles.
An inclusive search is presented for new heavy particle pairs produced in sqrt(s) = 7 TeV proton-proton collisions at the LHC using 4.7 +/- 0.1 inverse femtobarns of integrated luminosity. The selected events are analyzed in the 2D razor space of MR, an event-by-event indicator of the heavy particle mass scale, and R, a dimensionless variable related to the missing transverse energy. The third-generation sector is probed using the event heavy-flavor content. The search is sensitive to generic supersymmetry models with minimal assumptions about the superpartner decay chains. No excess is observ…
Five mutually exclusive searches for supersymmetry are presented based on events in which b jets and four W bosons are produced in proton-proton collisions at sqrt(s) = 8 TeV. The data, corresponding to an integrated luminosity of 19.5 inverse femtobarns, were collected with the CMS experiment at the CERN LHC in 2012. The five studies differ in the leptonic signature from the W boson decays, and correspond to all-hadronic, single-lepton, opposite-sign dilepton, same-sign dilepton, and greater-than-or-equal-to-3 lepton final states. The results of the five studies are combined to yield 95% conf…
A search for supersymmetry is presented based on events with at least one photon, jets, and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 35.9 fb$^{-1}$ and were recorded at the LHC with the CMS detector in 2016. The analysis characterizes signal-like events by categorizing the data into various signal regions based on the number of jets, the number of b-tagged jets, and the missing transverse momentum. No significant excess of events is observed with respect to the expectations fr…
This paper discusses supersymmetry discovery potential of the upgraded DØexperiment at the Tevatron $p\bar{p}$ collider. Six final states with large transverse energy (momentum) leptons or photons (with or without large transverse momentum imbalances) are studied. These final states are expected to have small backgrounds and are thereby ideal for new physics searches. Implications of the analyses of these final states on Gauge Mediated Supersymmetry Breaking models are discussed for integrated luminosities of 2 and 30 1/fb. This study demonstrates that a large class of supersymmetry models can…
A search is performed for an excess of events, over the standard model expectations, with a photon, a lepton, and large missing transverse energy in pp collisions at sqrt(s) = 7 TeV. Such events are expected in many new physics models, in particular a supersymmetric theory that is broken via a gauge-mediated mechanism, when the lightest charged and neutral gauginos are mass degenerate. The data sample used in this search corresponds to an integrated luminosity of 35 inverse picobarns collected with the CMS detector at the LHC. No evidence of such an excess above the standard model backgrounds,…
A search for the weak production of charginos and neutralinos into final states with three electrons or muons and missing transverse momentum is presented. The analysis uses 2.06 fb^-1 of sqrt(s) = 7 TeV proton-proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with standard model expectations in two signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric and simplified models. For the simplified m…
Recent advances in superconductor properties and superconducting magnet technology have made it possible to build cost-effective, high-performance dipoles with a field of 12 Tesla - 3 times the field strength of the Tevatron. Such magnets could be used to upgrade Fermilab's collider in its existing tunnel to a collision energy $\sqrt s$= 6 TeV and luminosity {$\cal L$}$>$ 10$^{33}$ cm$^{-2}$s$^{-1}$. We have calculated the parton luminosities for quark-antiquark and gluon-gluon scattering for the Tevatron, the Tripler, and LHC. In most models of the Higgs field and supersymmetry, the Tripler w…
In this note, recent results on the search for Gauge Mediated Supersymmetry Breaking (GMSB) and Anomaly Mediated Supersymmetry Breaking (AMSB) at the LEP and Tevatron colliders are summarized. We report on DZERO's search for GMSB in di-photon events with large missing transverse energy and discuss the sensitivity of similar searches based on future Tevatron integrated luminosities.
A search for direct chargino production in anomaly-mediated supersymmetry breaking scenarios is performed in pp collisions at sqrt(s) = 7 TeV using 4.7 fb^-1 of data collected with the ATLAS experiment at the LHC. In these models, the lightest chargino is predicted to have a lifetime long enough to be detected in the tracking detectors of collider experiments. This analysis explores such models by searching for chargino decays that result in tracks with few associated hits in the outer region of the tracking system. The transverse-momentum spectrum of candidate tracks is found to be consistent…
A search for R-parity violating supersymmetry in final states characterised by high jet multiplicity, at least one isolated light lepton and either zero or at least three $b$-tagged jets is presented. The search uses 139 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collision data collected by the ATLAS experiment during Run 2 of the Large Hadron Collider. The results are interpreted in the context of R-parity-violating supersymmetry models that feature gluino production, top-squark production, or electroweakino production. The dominant sources of background are estimated using a data-driven …
Results are reported from a search for supersymmetric particles in proton-proton collisions in the final state with a single lepton; multiple jets, including at least one b-tagged jet; and large missing transverse momentum. The search uses a sample of proton-proton collision data at sqrt(s) = 13 TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9 inverse femtobarns. The observed event yields in the signal regions are consistent with those expected from standard model backgrounds. The results are interpreted in the context of simplified models of sup…
We report a search for diphoton events with large missing transverse energy produced in ppbar collisions at sqrt(s)=1.96 TeV. The data were collected with the D0 detector at the Fermilab Tevatron Collider, and correspond to 6.3 fb-1 of integrated luminosity. The observed missing transverse energy distribution is well described by the standard model prediction, and 95% C.L. limits are derived on two realizations of theories beyond the standard model. In a gauge mediated supersymmetry breaking scenario, the breaking scale Lambda is excluded for Lambda < 124 TeV. In a universal extra dimension mo…
