A search for production of the supersymmetric partners of the top quark, top squarks, is presented. The search is based on proton-proton collision events containing multiple jets, no leptons, and large transverse momentum imbalance. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of 137 fb$^{-1}$. The targeted signal production scenarios are direct and gluino-mediated top squark production, including scenarios in which the top squark and neutralino masses are nearly degenerate. The search utilizes novel algorithms based on deep neural networks that identify hadronically decaying top quarks and W bosons, which are expected in many of the targeted signal models. No statistically significant excess of events is observed relative to the expectation from the standard model, and limits on the top squark production cross section are obtained in the context of simplified supersymmetric models for various production and decay modes. Exclusion limits as high as 1310 GeV are established at the 95% confidence level on the mass of the top squark for direct top squark production models, and as high as 2260 GeV on the mass of the gluino for gluino-mediated top squark production models. These results represent a significant improvement over the results of previous searches for supersymmetry by CMS in the same final state.
These proceedings summarize the results of four analyses which searched for squarks and gluinos in hadronic final states with missing transverse momentum in 2.3 fb$^{-1}$ of data in proton-proton collisions at $\sqrt{s}=13$ TeV collected in the year 2015 with the CMS detector at the CERN LHC. Each analysis is characterized by a different kinematic variable that is sensitive to the presence of invisible particles, e.g., $M_\text{T2}$, $α_{\text{T}}$, and razor variables. We observed no significant deviation from the standard model prediction and placed limits on the production cross sections an…
Searches for third-generation squarks in fully hadronic final states are presented using data samples corresponding to integrated luminosities of 19.4 or 19.7 inverse femtobarns, collected at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC. Three mutually exclusive searches are presented, each optimized for a different decay topology. They include a multijet search requiring one fully reconstructed top quark, a dijet search requiring one or two jets originating from b quarks, and a monojet search. No excesses above the standard model expectations are seen, and limits are set …
We report on a search for bottom squarks produced in pbarp collisions at sqrt(s) = 1.8 TeV using the D0 detector at Fermilab. Bottom squarks are assumed to be produced in pairs and to decay to the lightest supersymmetric particle (LSP) and a b quark with branching fraction of 100%. The LSP is assumed to be the lightest neutralino and stable. We set limits on the production cross section as a function of bottom squark mass and LSP mass.
A search for supersymmetric partners of quarks is performed in the topology of multijet events accompanied by at least one tau lepton decaying hadronically and large missing transverse energy. Approximately 1 fb-1 of ppbar collision data from the Fermilab Tevatron Collider at a center of mass energy of 1.96 TeV recorded by the D0 detector is analyzed. Results are combined with the previously published D0 inclusive search for squarks and gluinos. No evidence of physics beyond the standard model is found and lower limits on the squark mass up to 410 GeV are derived in the framework of minimal su…
The results of a search for squarks and gluinos using data from ppbar collisions recorded at a center-of-mass energy of 1.96 TeV by the D0 detector at the Fermilab Tevatron Collider are reported. The topologies analyzed consist of acoplanar-jet and multijet events with large missing transverse energy. No evidence for the production of squarks or gluinos was found in a data sample of 310 pb-1. Lower limits of 325 and 241 GeV were derived at the 95% C.L. on the squark and gluino masses, respectively, within the framework of minimal supergravity with tan(beta)=3, A0=0, and mu<0.
A search for the pair production of top squarks, each with R-parity-violating decays into two Standard Model quarks, is performed using 17.4 fb$^{-1}$ of $\sqrt{s}$ = 8 TeV proton-proton collision data recorded by the ATLAS experiment at the LHC. Each top squark is assumed to decay to a b- and an s-quark, leading to four quarks in the final state. Background discrimination is achieved with the use of b-tagging and selections on the mass and substructure of large-radius jets, providing sensitivity to top squark masses as low as 100 GeV. No evidence of an excess beyond the Standard Model backgro…
Weak scale supersymmetry is one of the best motivated and studied Standard Model extensions. It predicts the existence of new heavy coloured particles called squarks and gluinos which are the supersymmetric partners of the quarks and gluons, respectively. The poster summarises results on inclusive searches for supersymmetric squarks and gluinos in events containing jets and missing transverse momentum without leptons. The searches use the full data sample recorded in 2012 at $\sqrt{s}$=8~TeV centre-of-mass energy by the ATLAS experiment at the LHC.
A data sample corresponding to an integrated luminosity of 2.1 fb-1 collected by the D0 detector at the Fermilab Tevatron Collider was analyzed to search for squarks and gluinos produced in ppbar collisions at a center-of-mass energy of 1.96 TeV. No evidence for the production of such particles was observed in topologies involving jets and missing transverse energy, and 95% C.L. lower limits of 379 GeV and 308 GeV were set on the squark and gluino masses, respectively, within the framework of minimal supergravity with tan(beta)=3, A0=0, and mu<0. The corresponding previous limits are improved …
We report on a search for inclusive production of squarks and gluinos in ppbar collisions at sqrt{s}=1.96 TeV, in events with large missing transverse energy and multiple jets of hadrons in the final state. The study uses a CDF Run II data sample corresponding to 2 fb-1 of integrated luminosity. The data are in good agreement with the standard model predictions, giving no evidence for any squark or gluino component. In an R-parity conserving minimal supergravity scenario with A_0 = 0, mu < 0 and tanbeta = 5, 95% C.L. upper limits on the production cross sections in the range between 0.1 pb and…
A search for direct top squark pair production is presented. The search is based on proton-proton collision data at a center-of-mass energy of 13 TeV recorded by the CMS experiment at the LHC during 2016, 2017, and 2018, corresponding to an integrated luminosity of 137 fb$^{-1}$. The search is carried out using events with a single isolated electron or muon, multiple jets, and large transverse momentum imbalance. The observed data are consistent with the expectations from standard model processes. Exclusions are set in the context of simplified top squark pair production models. Depending on t…
We present results of the first search for like-sign dilepton (ee, eμ, μμ) events associated with multijets and large missing energy using 106 pb^-1 of data in p-pbar collisions at sqrt(s)=1.8 TeV collected during 1992-95 by the CDF experiment. Finding no events that pass our selection, we examine pair-production of gluinos and squarks in a constrained framework of the Minimal Supersymmetric Standard Model. At tan_beta = 2 and μ=-800 GeV/c^2, we set 95% confidence level limits of M(gluino) > 221 GeV/c^2 for M(gluino) \simeq M(squark), and M(gluino) > 168 GeV/c^2 for M(squark) \gg M(gluino), bo…
A search for squarks and gluinos in final states containing jets, missing transverse momentum and no high-pT electrons or muons is presented. The data represent the complete sample recorded in 2011 by the ATLAS experiment in 7 TeV proton-proton collisions at the Large Hadron Collider, with a total integrated luminosity of 4.7 fb^-1. No excess above the Standard Model background expectation is observed. Gluino masses below 860 GeV and squark masses below 1320 GeV are excluded at the 95% confidence level in simplified models containing only squarks of the first two generations, a gluino octet an…
A search for squarks and gluinos in events containing jets, missing transverse momentum and no electrons or muons is presented. The data were recorded in 2011 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 is observed in 1.04 fb^-1 of data. Gluino and squark masses below 700 GeV and 875 GeV respectively are excluded at the 95% confidence level in simplified models containing only squarks of the first two generations, a gluino octet and a massless neutralino. The exclusion limit increase…
A search for squarks and gluinos in final states containing jets, missing transverse momentum and no electrons or muons 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 35 inverse picobarns of analysed data. Gluino masses below 500 GeV are excluded at the 95% confidence level in simplified models containing only squarks of the first two generations, a gluino octet and a massless neutralino. The exclusion increases to 870 GeV for equal m…
A search is presented for direct top squark pair production in final states with one isolated electron or muon, jets, and missing transverse momentum in proton-proton collisions at sqrt(s) = 7 TeV. The measurement is based on 4.7 fb-1 of data collected with the ATLAS detector at the LHC. Each top squark is assumed to decay to a top quark and the lightest supersymmetric particle (LSP). The data are found to be consistent with Standard Model expectations. Top squark masses between 230 GeV and 440 GeV are excluded with 95% confidence for massless LSPs, and top squark masses around 400 GeV are exc…
This paper presents a search for the pair production of top squarks in events with a single isolated electron or muon, jets, large missing transverse momentum, and large transverse mass. The data sample corresponds to an integrated luminosity of 19.5 inverse femtobarns of pp collisions collected in 2012 by the CMS experiment at the LHC at a center-of-mass energy of sqrt(s) = 8 TeV. No significant excess in data is observed above the expectation from standard model processes. The results are interpreted in the context of supersymmetric models with pair production of top squarks that decay eithe…
The results of a search for squarks and gluinos in final states with an isolated electron or muon, multiple jets and large missing transverse momentum using proton--proton collision data at a center-of-mass energy of $\sqrt{s}$ = 13 TeV are presented. The dataset used was recorded during 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 36.1 $fb^{-1}$. No significant excess beyond the expected background is found. Exclusion limits at 95% confidence level are set in a number of supersymmetric scenarios, reaching masses up to 2.1 Te…
The results of a search for pair production of light top squarks are presented, using 4.7 fb^-1 of sqrt(s) = 7 TeV proton-proton collisions collected with the ATLAS detector at the Large Hadron Collider. This search targets top squarks with masses similar to, or lighter than, the top quark mass. Final states containing exclusively one or two leptons (e, mu), large missing transverse momentum, light-jets and b-jets are used to reconstruct the top squark pair system. Global mass scale variables are used to separate the signal from a large ttbar background. No excess over the Standard Model expec…
A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}$=13 TeV proton--proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. The results are interpreted in the context of various models where squarks and gluinos are pair-produced and the neutralino is the lightest supersymmetric particle. An exclusion l…
The results of a search for gluino and squark pair production with the pairs decaying via the lightest charginos into a final state consisting of two $W$ bosons, the lightest neutralinos ($\tildeχ^0_1$), and quarks, are presented. The signal is characterised by the presence of a single charged lepton ($e^{\pm}$ or $μ^{\pm}$) from a $W$ boson decay, jets, and missing transverse momentum. The analysis is performed using 139 fb$^{-1}$ of proton-proton collision data taken at a centre-of-mass energy $\sqrt{s}=13$ TeV delivered by the Large Hadron Collider and recorded by the ATLAS experiment. No s…
The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of $20.1 \rm{fb}^{-1}$ of proton-proton collision data at $\sqrt{s}=8$ TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via $\tilde{t} \rightarrow t \tildeχ_{1}^{0}$ or $\tilde{t}\rightarrow b\tildeχ_{1}^{\pm} \rightarrow b W^{\left(\ast\right)} \tildeχ_{1}^{0}$, where $\tildeχ_{1}^{0}$ ($\tildeχ_{1}^{\pm}$) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in e…
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 search uses data from proton-proton collisions at $\sqrt{s} =$ 13 TeV collected with the CMS detector, corresponding to an integrated luminosity of 137 fb$^{-1}$. Hypothetical signal events are efficiently separated from the dominant top quark pair production background with requirements on the significance of the missing transverse momentum and on transverse …
We search for physics beyond the standard model using events with a photon, two or more hadronic jets, and an apparent imbalance in transverse energy, in $p\bar{p}$ collisions at the Fermilab Tevatron at $\sqrt{s}=1.8$ TeV. Such events are predicted for production of supersymmetric particles. No excess is observed beyond expected background. For the parameter space of the minimal supersymmetric standard model with branching fraction $B(\tildeχ^0_2 \to γ\tildeχ^0_1) = 1$ and $m_{\tildeχ^0_2}-m_{\tildeχ^0_1}>20$ GeV, we obtain a 95% confidence level lower limit of 310 GeV for the masses of squar…
The results of a search for a supersymmetric partner of the top quark (top squark), pair-produced in proton-proton collisions at sqrt(s) = 8 TeV, are presented. The search, which focuses on R-parity violating, chargino-mediated decays of the top squark, is performed in final states with low missing transverse momentum, two oppositely charged electrons or muons, and at least five jets. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 inverse femtobarns collected with the CMS detector at the LHC in 2012. The data are found to be in agreement with the standard mod…
Results are presented from a search for the pair production of third-generation squarks in proton-proton collision events with two-body decays to bottom or charm quarks and a neutralino, which produces a significant imbalance in the transverse momentum. The search is performed using 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. No statistically significant excess of events is observed beyond the expected contribution from standard model processes. Exclusion limits are…
A search for pair production of third-generation scalar leptoquarks and supersymmetric top quark partners, top squarks, in final states involving tau leptons and bottom quarks is presented. The search uses events from a data sample of proton-proton collisions corresponding to an integrated luminosity of 19.7 inverse femtobarns, collected with the CMS detector at the LHC with sqrt(s) = 8 TeV. The number of observed events is found to be in agreement with the expected standard model background. Third-generation scalar leptoquarks with masses below 740 GeV are excluded at 95% confidence level, as…
A search for pair production of bottom squarks in events with hadronically decaying $τ$-leptons, $b$-tagged jets and large missing transverse momentum is presented. The analyzed dataset is based on proton-proton collisions at $\sqrt{s}$ = 13 TeV delivered by the Large Hadron Collider and recorded by the ATLAS detector from 2015 to 2018, and corresponds to an integrated luminosity of 139 fb$^{-1}$. The observed data are compatible with the expected Standard Model background. Results are interpreted in a simplified model where each bottom squark is assumed to decay into the second-lightest neutr…
A search for squarks and gluinos in final states containing hadronic jets, missing transverse momentum but no electrons or muons is presented. The data were recorded in 2015 by the ATLAS experiment in $\sqrt{s}=$ 13 TeV proton--proton collisions at the Large Hadron Collider. No excess above the Standard Model background expectation was observed in 3.2 fb$^{-1}$ of analyzed data. Results are interpreted within simplified models that assume R-parity is conserved and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is…
Search for top squark pair production in a final state with at least one hadronically decaying tau lepton in proton-proton collisions at $\sqrt{s}$ = 13 TeV
A search for direct pair production of the supersymmetric partner of the top quark, decaying via a scalar tau to a nearly massless gravitino, has been performed using 20 fb$^{-1}$ of proton-proton collision data at $\sqrt{s}=8$ TeV. The data were collected by the ATLAS experiment at the LHC in 2012. Top squark candidates are searched for in events with either two hadronically decaying tau leptons, one hadronically decaying tau and one light lepton, or two light leptons. No significant excess over the Standard Model expectation is found. Exclusion limits at 95% confidence level are set as a fun…
A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded by the ATLAS experiment in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}$ = 13 TeV during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb$^{-1}$. The results are interpreted in the context of various $R$-parity-conserving models where squarks and gluinos are produced in pairs or in association and a neutral…
Searches are presented for direct production of top or bottom squark pairs in proton-proton collisions at the CERN LHC. Two searches, based on complementary techniques, are performed in all-jet final states that are characterized by a significant imbalance in transverse momentum. An additional search requires the presence of a charged lepton isolated from other activity in the event. The data were collected in 2015 at a centre-of-mass energy of 13 TeV with the CMS detector and correspond to an integrated luminosity of 2.3 inverse femtobarns. No statistically significant excess of events is fou…
A search for pair production of the supersymmetric partner of the top quark, the top squark, in proton-proton collision events at $\sqrt{s} =$ 13 TeV is presented in a final state containing hadronically decaying tau leptons and large missing transverse momentum. This final state is highly sensitive to high-$\tanβ$ or higgsino-like scenarios in which decays of electroweak gauginos to tau leptons are dominant. The search uses a data set corresponding to an integrated luminosity of 77.2 fb$^{-1}$, which was recorded with the CMS detector during 2016 and 2017. No significant excess is observed wi…
A search for top squark pair production in pp collisions at sqrt(s) = 13 TeV is performed using events with a single isolated electron or muon, jets, and a large transverse momentum imbalance. The results are based on data collected in 2016 with the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9 inverse femtobarns. No significant excess of events is observed above the expectation from standard model processes. Exclusion limits are set in the context of supersymmetric models of pair production of top squarks that decay either to a top quark and a neutralino or to a b…
The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of $20.1 \rm{fb}^{-1}$ of proton-proton collision data at $\sqrt{s}=8$ TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via $\tilde{t} \rightarrow t \tildeχ_{1}^{0}$ or $\tilde{t}\rightarrow b\tildeχ_{1}^{\pm} \rightarrow b W^{\left(\ast\right)} \tildeχ_{1}^{0}$, where $\tildeχ_{1}^{0}$ ($\tildeχ_{1}^{\pm}$) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in e…
We calculate the rates for inclusive hadronic decay of the three $χ_{bJ}$ states into a pair of light bottom squarks as a function of the masses of the bottom squark and the gluino. We include color-singlet and color-octet configurations. The color-octet contribution is found to be insignificant for the $χ_{b0}$ but can dominate in the $χ_{b2}$ case if current lattice estimates are used for the color-octet matrix element. In comparison with the standard model values, bottom squark decays can increase the predicted hadronic width of the $χ_{b0}$ by as much as 35%, for very small bottom squark m…
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 mass difference between the top squark and the neutralino being close to the top quark mass. The search is performed with 35.9 fb$^{-1}$ of proton-proton collisions at a centre-of-mass energy of $\sqrt{s} =$ 13 TeV, collected by the CMS detector in 2016, using events containing one electron-muon pair with opposite charge. The search is based on a precise est…
A search for direct pair production of top squarks in final states with two tau leptons, $b$-jets, and missing transverse momentum is presented. The analysis is based on proton-proton collision data at $\sqrt{s} = 13$ TeV corresponding to an integrated luminosity of 36.1 fb$^{-1}$ recorded with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. Two exclusive channels with either two hadronically decaying tau leptons or one hadronically and one leptonically decaying tau lepton are considered. No significant deviation from the Standard Model predictions is observed in the data. Th…
A search for supersymmetry through the direct pair production of top squarks, with Higgs (H) or Z bosons in the decay chain, is performed using a data sample of proton-proton collisions at sqrt(s) = 8 TeV collected in 2012 with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 19.5 inverse femtobarns. The search is performed using a selection of events containing leptons and bottom-quark jets. No evidence for a significant excess of events over the standard model background prediction is observed. The results are interpreted in the context of simplified supersy…
This paper presents a search for direct top squark pair production in events with missing transverse momentum plus either a pair of jets consistent with Standard Model Higgs boson decay into $b$-quarks or a same-flavour opposite-sign dilepton pair with an invariant mass consistent with a $Z$ boson. The analysis is performed using the proton-proton collision data at $\sqrt{s}=13$ TeV collected with the ATLAS detector during the LHC Run-2, corresponding to an integrated luminosity of 139 fb$^{-1}$. No excess is observed in the data above the Standard Model predictions. The results are interprete…
Results of a search for supersymmetry via direct production of third-generation squarks are reported, using $20.3$ fb$^{-1}$ of proton-proton collision data at $\sqrt{s} = 8$ TeV recorded by the ATLAS experiment at the LHC in 2012. Two different analysis strategies based on monojet-like and $c$-tagged event selections are carried out to optimize the sensitivity for direct top squark pair production in the decay channel to a charm quark and the lightest neutralino ($\tilde{t}_1 \to c + \tildeχ_{1}^{0}$) across the top squark--neutralino mass parameter space. No excess above the Standard Model b…
We analyse the prospect of extending the reach for squarks and gauginos via associated production at a $\sqrt{s} = 100$ TeV proton-proton collider, given 3 ab$^{-1}$ integrated luminosity. Depending on the gluino mass, the discovery reach for squarks in associated production with a gluino can be up to 37 TeV for compressed spectra (small gluino-LSP mass splitting), and up to 32 TeV for non-compressed spectra. The discovery reach for Winos can be up to between 3.5 and 6 TeV depending on squark masses and Wino decay kinematics. Binos of up to 1.7 TeV could similarly be discovered. Squark-gaugino…
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(…
The results of a search for pair production of supersymmetric partners of the Standard Model third-generation quarks are reported. This search uses 20.1 fb-1 of pp collisions at sqrt{s}=8 TeV collected by the ATLAS experiment at the Large Hadron Collider. The lightest bottom and top squarks (b1 and t1 respectively) are searched for in a final state with large missing transverse momentum and two jets identified as originating from b-quarks. No excess of events above the expected level of Standard Model background is found. The results are used to set upper limits on the visible cross section fo…
Results are presented from a search for the pair production of third-generation scalar and vector leptoquarks, as well as for top squarks in R-parity-violating supersymmetric models. In either scenario, the new, heavy particle decays into a tau lepton and a b quark. The search is based on a data sample of pp collisions at sqrt(s) = 7 TeV, which is collected by the CMS detector at the LHC and corresponds to an integrated luminosity of 4.8 inverse femtobarns. The number of observed events is found to be in agreement with the standard model prediction, and exclusion limits on mass parameters are …
The result of a search for pair production of the supersymmetric partner of the Standard Model bottom quark ($\tilde{b}_1$) is reported. The search uses 3.2 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=$13 TeV collected by the ATLAS experiment at the Large Hadron Collider in 2015. Bottom squarks are searched for in events containing large missing transverse momentum and exactly two jets identified as originating from $b$-quarks. No excess above the expected Standard Model background yield is observed. Exclusion limits at 95% confidence level on the mass of the bottom squark are derived in phenome…
A search for pair production of supersymmetric particles in events with two oppositely charged leptons (electrons or muons) and missing transverse momentum is reported. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} =$ 13 TeV collected with the CMS detector during the 2016 data taking period at the LHC. No significant deviation is observed from the predicted standard model background. The results are interpreted in terms of several simplified models for chargino and top squark pair production, assuming $R$-parity conservation …
A search for squarks and gluinos in final states containing high-$p_{\rm T}$ jets, missing transverse momentum and no electrons or muons is presented. The data were recorded in 2012 by the ATLAS experiment in $\sqrt{s}=8$ TeV proton-proton collisions at the Large Hadron Collider, with a total integrated luminosity of $20.3 \mathrm{fb}^{-1}$. No significant excess above the Standard Model expectation is observed. Results are interpreted in a variety of simplified and specific supersymmetry-breaking models assuming that R-parity is conserved and that the lightest neutralino is the lightest super…
We present preliminary results on a search for squarks and gluinos in proton-antiproton collisions with a center-of-mass energy of 1.96 TeV and based on 1.1 fb-1 of data collected by the CDF detector in the Tevatron Run II. Events with multiple jets of hadrons and large missing transverse energy in the final state are studied within the framework of minimal supergravity and assuming R-parity conservation. No excess with respect to Standard Model predictions is observed and new limits on the gluino and squark masses are extracted.
Search for direct pair production of top squarks in $pp$ collisions at $\sqrt{s}= 13$ TeV and $13.6$ TeV in events with two oppositely charged leptons using the ATLAS detector
EUROPEAN ORGANISATION FOR NUCLEAR RESEARCH (CERN)(欧洲核子研究中心(CERN))
An inclusive search is performed for supersymmetry in final states containing jets and an apparent imbalance in transverse momentum, pt[miss], due to the production of unobserved weakly interacting particles in pp collisions at a centre-of-mass energy of 8 TeV. The data, recorded with the CMS detector at the CERN LHC, correspond to an integrated luminosity of 18.5 inverse femtobarns. The dimensionless kinematic variable alpha[T] is used to discriminate between events with genuine pt[miss] associated with unobserved particles and spurious values of pt[miss] arising from jet energy mismeasuremen…
In the general MSSM, first and second generation squarks and gluinos may be sufficiently light to be produced and studied at $e^+e^-$ colliders operating in the 0.5-1 TeV energy range. After a reminder that the MSSM is {\it not} the same as mSUGRA, we provide a brief overview of these possibilities within this more general framework
The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider (LHC) are reported. The search is based on proton-proton collision data at a centre-of-mass energy $\sqrt{s} = 8$ TeV collected in 2012, corresponding to an integrated luminosity of 20 fb$^{-1}$. No significant excess above the Standard Model expectation is observed. Limits are set on the parameters of a minimal universal extra dimensions model, excluding a compactification radius of…
A search is presented for direct top squark pair production using events with at least two leptons including a same-flavour opposite-sign pair with invariant mass consistent with the $Z$ boson mass, jets tagged as originating from $b$-quarks and missing transverse momentum. The analysis is performed with proton-proton collision data at $\sqrt{s}=8$ TeV collected with the ATLAS detector at the LHC in 2012 corresponding to an integrated luminosity of 20.3 fb$^{-1}$. No excess beyond the Standard Model expectation is observed. Interpretations of the results are provided in models based on the dir…
Search for squarks and gluinos in $pp$ collisions at $\sqrt{s} = 13$ TeV and $13.6$ TeV in events with $τ$-leptons, jets and missing transverse momentum using the ATLAS detector
EUROPEAN ORGANISATION FOR NUCLEAR RESEARCH (CERN)(欧洲核子研究中心(CERN))
利用 ATLAS 探测器在 13 TeV 和 13.6 TeV 撞击数据中,研究 squarks 和 gluinos 的产生,排除了部分高质子质量范围。
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 $\sqrt{s}=13$ TeV collected by the ATLAS detector at the Large Hadron Collider. To cover a range of mass differences between the top squark $\tilde{t}$ and lighter supersymmetric particles, four possible decay modes of the top squark are targeted with dedicated selections: the decay $\tilde{t} \rightarrow b \tildeχ_{1}^{\pm}$ into a $b$-quark and the lightest chargino with …
The results of a search for the direct pair production of top squarks, the supersymmetric partner of the top quark, in final states with one isolated electron or muon, several energetic jets, and missing transverse momentum are reported. The analysis also targets spin-0 mediator models, where the mediator decays into a pair of dark-matter particles and is produced in association with a pair of top quarks. The search uses data from proton-proton collisions delivered by the Large Hadron Collider in 2015 and 2016 at a centre-of-mass energy of $\sqrt{s}=13$ TeV and recorded by the ATLAS detector, …
A measurement of spin correlation in $t\bar{t}$ production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb$^{-1}$. The correlation between the top and antitop quark spins is extracted from dilepton $t\bar{t}$ events by using the difference in azimuthal angle between the two charged leptons in the laboratory frame. In the helicity basis the measured degree of correlation corresponds to $A_{helicity} = 0.38 \pm 0.04$, in agreement with the S…
A search is performed for heavy particle pairs produced in sqrt(s) = 7 TeV proton-proton collisions with 35 inverse picobarns of data collected by the CMS experiment at the LHC. The search is sensitive to squarks and gluinos of generic supersymmetry models, provided they are kinematically accessible, with minimal assumptions on properties of the lightest superpartner particle. The kinematic consistency of the selected events is tested against the hypothesis of heavy particle pair production using the dimensionless razor variable R, related to the missing transverse energy. The new physics sign…
A summary is presented of ATLAS searches for gluinos and first- and second-generation squarks in final states containing jets and missing transverse momentum, with or without leptons or b-jets, in the $\sqrt{s}$ = 8 TeV data set collected at the Large Hadron Collider in 2012. This paper reports the results of new interpretations and statistical combinations of previously published analyses, as well as a new analysis. Since no significant excess of events over the Standard Model expectation is observed, the data are used to set limits in a variety of models. In all the considered simplified mod…