Improving the sensitivity of stop searches with on-shell constrained invariant mass variables

Abstract

The search for light stops is of paramount importance, both in general as a promising path to the discovery of beyond the standard model physics and more specifically as a way of evaluating the success of the naturalness paradigm. While the LHC experiments have ruled out much of the relevant parameter space, there are "stop gaps", i.e., values of sparticle masses for which existing LHC analyses have relatively little sensitivity to light stops. We point out that techniques involving on-shell constrained M_2 variables can do much to enhance sensitivity in this region and hence help close the stop gaps. We demonstrate the use of these variables for several benchmark points and describe the effect of realistic complications, such as detector effects and combinatorial backgrounds, in order to provide a useful toolkit for light stop searches in particular, and new physics searches at the LHC in general.

49 pages, 28 figures, revised version published in JHEP, references added

References in corpus (38)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• PYTHIA 6.4 Physics and Manual
• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Search for squarks and gluinos with the ATLAS detector in final states with jets and missing transverse momentum using $\sqrt{s}=8$ TeV proton--proton collision data
• Search for new physics in the multijet and missing transverse momentum final state in proton-proton collisions at sqrt(s) = 8 TeV
• Gluino Stransverse Mass
• Measuring superparticle masses at hadron collider using the transverse mass kink
• Search for pair-produced third-generation squarks decaying via charm quarks or in compressed supersymmetric scenarios in $pp$ collisions at $\sqrt{s}=8$TeV with the ATLAS detector
• Using Subsystem MT2 for Complete Mass Determinations in Decay Chains with Missing Energy at Hadron Colliders
• Search for top squark pair production in final states with one isolated lepton, jets, and missing transverse momentum in $\sqrt{s}=$ 8 TeV pp collisions with the ATLAS detector
• Search for direct top-squark pair production in final states with two leptons in pp collisions at sqrt(s)=8TeV with the ATLAS detector
• Measurement of the $t\bar{t}$ production cross-section using $e\mu$ events with $b$-tagged jets in $pp$ collisions at $\sqrt{s}=7$ and 8 TeV with the ATLAS detector
• Search for supersymmetry at $\sqrt{s}=13$ TeV in final states with jets and two same-sign leptons or three leptons with the ATLAS detector
• Stop the Top Background of the Stop Search
• Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• Search for new physics in events with same-sign dileptons and b-tagged jets in pp collisions at sqrt(s) = 7 TeV
• M_T2-assisted on-shell reconstruction of missing momenta and its application to spin measurement at the LHC
• Search for strong production of supersymmetric particles in final states with missing transverse momentum and at least three b-jets at $\sqrt{s}=$ 8 TeV proton-proton collisions with the ATLAS detector
• Search for top-squark pairs decaying into Higgs or Z bosons in pp collisions at sqrt(s) = 8 TeV
• Mass Determination of New States at Hadron Colliders
• Polarized Tops from Stop Decays at the LHC
• Light Stop Searches at the LHC in Events with One Hard Photon or Jet and Missing Energy
• Search for direct top squark pair production in events with a Z boson, b-jets and missing transverse momentum in sqrt(s)=8 TeV pp collisions with the ATLAS detector
• Closing the stop gap
• Light Stop Searches at the LHC in Events with two b-Jets and Missing Energy
• Stop on Top
• On-shell constrained $M_2$ variables with applications to mass measurements and topology disambiguation
• Measuring the top quark mass with m_T2 at the LHC
• Sneaky light stop
• Reconstructing singly produced top partners in decays to $\mathbf{Wb}$
• Discovery reach for generic supersymmetry at the LHC: MT2 versus missing transverse momentum selections for pMSSM searches
• Dark decay of the top quark
• 1-loop SQCD corrections to the decay of top-squarks to charm and neutralino in the generic MSSM
• Top jets as a probe of degenerate stop-NLSP LSP scenario in the framework of cMSSM
• Invisible dark gauge boson search in top decays using a kinematic method
• Deconstructed Transverse Mass Variables
• SUSY searches at the Tevatron

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• Resolving Combinatorial Ambiguities in Dilepton $t\bar{t}$ Event Topologies with Constrained $M_2$ Variables
• Detecting kinematic boundary surfaces in phase space: particle mass measurements in SUSY-like events
• Two Light Stops in the NMSSM and the LHC
• Is the Machine Smarter than the Theorist: Deriving Formulas for Particle Kinematics with Symbolic Regression
• Testing Invisible Momentum Ansatze in Missing Energy Events at the LHC
• Identifying Phase Space Boundaries with Voronoi Tessellations
• Top quark mass determination from the energy peaks of b-jets and B-hadrons at NLO QCD
• Singularity Variables for Missing Energy Event Kinematics
• Enhancing the discovery prospects for SUSY-like decays with a forgotten kinematic variable
• Demystifying the compressed top squark region with kinematic variables
• Light stop in the MSSM after LHC Run 1
• Measuring Masses in Semi-Invisible Final States at Electron-Positron Colliders
• Light top squarks in $U(1{)}_R$-lepton number model with a right handed neutrino and the LHC
• Kinematic Focus Point Method for Particle Mass Measurements in Missing Energy Events
• On the ATLAS Top Mass Measurements and the Potential for Stealth Stop Contamination
• Exploring the nearly degenerate stop region with sbottom decays
• Search for Heavy Stops with Merged Top-Jets
• $M_{TN}$ is all you need: production of multiple semi-invisible resonances at hadron colliders
• Light stop squarks and b-tagging