Pos(EPS-HEP 2013)161 ∗ [email protected] Speaker

Searches for Supersymmetry Oliver Buchmueller∗ Imperial College London E-mail: <a href="mailto:[email protected]" target="_blank">[email protected] </a>on behalf of the ATLAS and CMS Collaborations Since its first physics operation in 2010, the Large Hadron Collider at CERN has set a precedent in searches for supersymmetry. This proceeding report provides a brief overview on the current status of searches for supersymmetry at the LHC. The European Physical Society Conference on High Energy Physics -EPS-HEP2013 18-24 July 2013 Stockholm, Sweden ∗Speaker. <ul style="display: flex;"><li style="flex:1">c</li><li style="flex:1">ꢀ Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. </li></ul><a href="/goto?url=http://pos.sissa.it/" target="_blank">http://pos.sissa.it/ </a>Searches for Supersymmetry Oliver Buchmueller <ul style="display: flex;"><li style="flex:1">MSUGRA/CMSSM: tan(ꢀ) = 30, A = -2m0, µ > 0 </li><li style="flex:1">Status: SUSY 2013 </li></ul>01000 900 800 700 600 500 400 300 ꢃꢂ95% CL limits.ꢄSUSY theory not included. LSP Expected ATLAS Preliminary <ul style="display: flex;"><li style="flex:1">L dt = 20.1 - 20.7 fb-1 </li><li style="flex:1">s = 8 TeV </li></ul>0-lepton, 2-6 jets ATLAS-CONF-2013-047 Observed Expected ,ꢁ0-lepton, 7-10 jets arXiv: 1308.1841 Observed Expected 0-1 lepton, 3 b-jets ATLAS-CONF-2013-061 Observed Expected 1-lepton + jets + MET ATLAS-CONF-2013-062 Observed Expected 1-2 taus + jets + MET ATLAS-CONF-2013-026 Observed Expected 2-SS-leptons, 0 - ꢅ 3 b-jets Observed ATLAS-CONF-2013-007 <ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">1000 </li><li style="flex:1">2000 </li><li style="flex:1">3000 </li><li style="flex:1">4000 </li><li style="flex:1">5000 </li><li style="flex:1">6000 </li></ul>m0 [GeV] Figure 1: 95% C.L. limits for different ATLAS searches defined in the CMSSM 1. Introduction The landscape of searches for Supersymmetry (SUSY) has changed dramatically since the Large Hadron Collider (LHC) at CERN began physics operation in 2010. By the end of 2011 the experiments CMS [1] and ATLAS [2] had collected about 5 fb−1 of integrated luminosity each at a center-of-mass energy of 7 TeV. In 2012 the LHC operated at a center-of-mass energy of 8 TeV and each experiment collected approximately 20 fb−1 of data at this energy. In this proceeding report I will focus on the status of searches for SUSY at the LHC. A more detailed and comprehensive overview is provided in the September 2013 update of the experimental review for SUSY searches in the PDG [3]. For more details on LEP and Tevatron results see also earlier PDG reviews [4]. 2. Summary of R-parity conserving searches If the multiplicative quantum number of R-parity, R = (−1)3(B−L)+2S, where B and L are baryon and lepton numbers and S is the spin, is conserved the lightest SUSY particle (LSP) is stable and often assumed to be a weakly interacting massive particle. The LSP escapes undetected through the experiment, leading to final states with several hadronic jets, large missing transverse energy, and possible leptons and photons in the final state. 2Searches for Supersymmetry Oliver Buchmueller mLSP! [GeV]! Direct squark! Gluino mediated ! mSUSY = mq˜ mSUSY = mg˜ q˜ ! g˜ ! 1000! !1u˜ ! ATLAS-CONF-2013-047 ! L100¯˜b ! !g˜ ! 0CMS-PAS-SUS-12-024! ÃTLAS-CONF-2013-037 ! t ! 0¯g˜ ! !1750! Direct stop in “gap”! ATLAS-CONF-2013-061! mSUSY = mt˜ 0ÃTLAS-CONF-2013-068! !!t ! 0CMS-PAS-SUS! -13-011! ˜t ! !!Direct slepton! 500! lL ! ˜Direct χ! ±/χ02 BR=100%! 1ATLAS-CONF-! 02mSUSY = mχ± = mχ 12013-049! all limits are ! lR ! õbserved nominal 95% CLs limits! RP conserved ! χ±1 χ2(light l) 0˜χ±1 χ2(heavy l) 0˜250! CMS-PAS-SUS-13-006! mSUSY! [GeV]! 0! 0! <ul style="display: flex;"><li style="flex:1">1250! </li><li style="flex:1">1500! </li></ul>37 <ul style="display: flex;"><li style="flex:1">750! </li><li style="flex:1">1000! </li></ul><ul style="display: flex;"><li style="flex:1">500! </li><li style="flex:1">250! </li></ul>Figure 2: Illustrative summary plot for the most important simplified model limits. ATLAS and CMS have performed many searches looking for R-parity conserving SUSY sig- natures. Figure 1 shows limits in the framework of the CMSSM, assuming tanβ = 30, A0 = −2m0, and µ > 0, for several ATLAS searches. In this constrained SUSY model gluino masses below ≈1.3 TeV are excluded for all squark masses, while for equal gluino and squark masses, the limit is around 1.7 TeV. Furthermore, squark masses below 1.6 TeV are excluded for all gluino masses. The CMS collaboration has not yet provided an interpretation of their 8 TeV searches in the CMSSM but the performance is expected to be very similar. Another important interpretation approach, even less dependent on fundamental assumptions, is the characterisation of the searches in terms of simplified models. Such models assume a limited set of SUSY particle production and decay modes and leave open the possibility to vary masses and other parameters freely. Today, ATLAS and CMS have adopted simplified models as the primary framework to provide interpretations of their searches. Figure 2 shows an illustrative overview of limits for the most important simplified models that are considered. For gluino masses rather similar limits, ranging from 1.2 TeV to 1.4 TeV, are obtained from different model assumptions. This shows that the LHC is probing a large region in SUSY parameter space for direct gluino production at the 1 TeV scale and beyond. Limits defined in simplified models on squark mass are not only much weaker but also vary strongly depending on the assumed properties of the decay chain. As shown in Figure 2, limits on direct squark production only go up 800 GeV under the assumption of an eightfold mass- 3Searches for Supersymmetry Oliver Buchmueller <ul style="display: flex;"><li style="flex:1">Summary of CMS RPV SUSY Results* </li><li style="flex:1">EPSHEP 2013 </li></ul>~g → qllν λλSUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb EXO-12-049 L=19.5 /fb EXO-12-049 L=19.5 /fb SUS-13-013 L=19.5 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-13-003 L=19.5 9.2 /fb SUS-12-027 L=9.2 /fb SUS-13-003 L=19.5 9.2 /fb SUS-13-003 L=19.5 /fb EXO-12-002 L=4.8 /fb 122 ~g → qllν g → qllν λ123 g → qbtµ λ' ~233 ~Prompt LSP decays 231 ~g → qbtµ λ' 233 ~g → qqb λ'' 113/223 ~g → qqq λ'' 112 323 ~g → tbs λ'' ~g → qqqq λ'' q → qllν λ112 ~122 ~q → qllν λq → qllν λ123 q → qbtµ λ' ~233 ~231 ~q → qbtµ λ' 233 112 122 ~qR → qqqq λ'' ~tR → µeνt λλ~s = 7 TeV s = 8 TeV tR → µτνt tR → µτνt λ123 ~233 ~tR → tbtµ λ' CMS Preliminary t → bτ λ'233 ~333 <ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">200 </li><li style="flex:1">400 </li><li style="flex:1">600 </li><li style="flex:1">800 </li><li style="flex:1">1000 </li><li style="flex:1">1200 </li><li style="flex:1">1400 </li><li style="flex:1">1600 </li><li style="flex:1">1800 </li></ul>*Observed limits, theory uncertainties not included Only a selection of available mass limits Probe *up to* the quoted mass limit Mass scales [GeV] Figure 3: Summary plot for R-parity violating CMS searches. The corresponding ATLAS results are similar. degeneracy for first and second generation squarks. If, however, only a single squark is assumed to be light, this limit weakens to only ≈ 450 GeV for the best possible scenario of very light neutralinos. For the production of single bottom squarks the best limit improves to around 650 GeV due to better control of the SM background via the identification of b quarks in the final state. For top squarks the situation is even more complex because of the many different decay chains that must be considered. While in the best case limits of up to 700 GeV are possible, there are also regions in SUSY parameter space where even for light neutralinos top squarks above a few hundred GeV cannot be ruled out by the LHC searches. Pair production of chargino, neutralinos, and sleptons at the LHC, for masses of several hundreds of GeV, is at least two orders of magnitude smaller than for coluored SUSY particles (e.g. top squark pair production). Therefore, high statistics data samples are required to constrain these SUSY particles. Today, depending on the assumed scenario limits on these particles vary from around 700 GeV in the most optimistic case to only a few hundred GeV for more pessimistic decay topologies. Much more data will be needed to push these limits above the 1 TeV scale. Further results of SUSY searches can be obtained from the public result pages of ATLAS [5] and CMS [6]. 3. Summary of R-parity violating searches If R-parity is violated, new terms λi jk, λi0jk and λi0j0k appear in the super potential, where i jk are 4Searches for Supersymmetry Oliver Buchmueller Preliminary ATLAS SUSY Searches* - 95% CL Lower Limits Status: SUSY 2013 ATLAS R√<ul style="display: flex;"><li style="flex:1">L dt = (4.6 - 22.9) fb−1 </li><li style="flex:1">s = 7, 8 TeV </li></ul>REmiss L dt[fb−1 ]e, µ, τ, γ <ul style="display: flex;"><li style="flex:1">Model </li><li style="flex:1">Jets </li><li style="flex:1">Mass limit </li><li style="flex:1">Reference </li></ul>T2-6 jets 3-6 jets 7-10 jets 2-6 jets 2-6 jets 3-6 jets 0-3 jets 2-4 jets 0-2 jets -˜q, g˜ ˜g m(q˜)=m(g˜) any m(q˜) any m(q˜) MSUGRA/CMSSM MSUGRA/CMSSM MSUGRA/CMSSM <ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">Yes </li></ul>Yes Yes Yes Yes 20.3 20.3 20.3 20.3 20.3 20.3 20.3 4.7 1.7 TeV ATLAS-CONF-2013-047 ATLAS-CONF-2013-062 1308.1841 1 e, µ 1.2 TeV 1.1 TeV ˜g 0sehχ˜0 q˜q˜, q˜→q 1˜q χ˜0 0740 GeV ATLAS-CONF-2013-047 ATLAS-CONF-2013-047 ATLAS-CONF-2013-062 ATLAS-CONF-2013-089 1208.4688 m( 1)=0 GeV crχ˜0 g˜g˜, g˜→qq¯ 1˜g χ˜0 01.3 TeV m( 1)=0 GeV ae1 e, µ 2 e, µ 2 e, µ ˜g χ˜0 χ˜± χ˜0 χ˜± ±χ˜01 Yes -1.18 TeV 1.12 TeV 1.24 TeV m( 1)<200 GeV, m( )=0.5(m( 1)+m(g˜)) g˜g˜, g˜→qq 1 →qqW χ˜0 ˜g χ˜0 Sg˜g˜, g˜→qq(ℓℓ/ℓν/νν) m( 1)=0 GeV 1˜e˜g tanβ<15 <ul style="display: flex;"><li style="flex:1">GMSB (ℓ NLSP) </li><li style="flex:1">Yes </li></ul>Yes Yes Yes Yes Yes Yes vi˜˜g tanβ >18 GMSB (ℓ NLSP) GGM (bino NLSP) GGM (wino NLSP) 1-2 τ 2 γ 1 e, µ + γ γ20.7 4.8 1.4 TeV 1.07 TeV ATLAS-CONF-2013-026 1209.0753 sχ˜0 ul˜g m( 1)>50 GeV c-χ˜0 nI˜g ATLAS-CONF-2012-144 1211.1167 4.8 4.8 619 GeV m( 1)>50 GeV χ˜0 GGM (higgsino-bino NLSP) GGM (higgsino NLSP) Gravitino LSP ˜g 1 b 0-3 jets mono-jet 900 GeV m( 1)>220 GeV ˜2 e, µ (Z) 0˜g 5.8 10.5 690 GeV 645 GeV <ul style="display: flex;"><li style="flex:1">m(H)>200 GeV </li><li style="flex:1">ATLAS-CONF-2012-152 </li></ul><ul style="display: flex;"><li style="flex:1">ATLAS-CONF-2012-147 </li><li style="flex:1">m(g˜)>10−4 eV </li></ul>F1/2 scale .neg01.de¯χ˜0 χ˜ ˜g ˜g ˜g ˜g <ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">3 b </li></ul>7-10 jets Yes Yes Yes Yes 20.1 20.3 20.1 20.1 1.2 TeV 1.1 TeV 1.34 TeV 1.3 TeV ATLAS-CONF-2013-061 1308.1841 m( 1)<600 GeV g˜→bb χ˜0 χ˜0 ¯g˜→tt 10m( 1) <350 GeV χ˜0 0-1 e, µ 0-1 e, µ χ˜0 m¯g˜→tt 13 b 3 b ATLAS-CONF-2013-061 ATLAS-CONF-2013-061 m( 1)<400 GeV χ˜+ χ˜0 ¯g˜→bt 1m( 1)<300 GeV χ˜0 χ˜0 1308.2631 ˜b1 ˜b1 ˜t1 ˜t1 ˜t1 ˜t1 ˜t1 ˜t1 ˜˜b1 ˜˜b˜˜0 2 b 0-3 b 1-2 b 0-2 jets 2 jets Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes 20.1 20.7 4.7 100-620 GeV 275-430 GeV m( 1)<90 GeV b1 b1, b1→b 1χ˜± ˜χ˜± χ˜0 2 e, µ (SS) 1-2 e, µ 2 e, µ ATLAS-CONF-2013-007 1208.4305, 1209.2102 1, b1→t <ul style="display: flex;"><li style="flex:1">m( 1 )=2 m( </li><li style="flex:1">)</li></ul>11<ul style="display: flex;"><li style="flex:1">s</li><li style="flex:1">n</li></ul>kroiχ˜± χ˜0 ˜ ˜ t1 t1(light), t1→b 110-167 GeV 130-220 GeV m( 1)=55 GeV 1taucχ˜0 χ˜0 χ˜± <ul style="display: flex;"><li style="flex:1">˜</li><li style="flex:1">˜</li></ul><ul style="display: flex;"><li style="flex:1">˜ ˜ </li><li style="flex:1">˜</li></ul>20.3 20.3 20.1 20.7 20.5 20.3 20.7 20.7 ATLAS-CONF-2013-048 ATLAS-CONF-2013-065 1308.2631 <ul style="display: flex;"><li style="flex:1">m( 1) =m(t1)-m(W)-50 GeV, m(t1)<<m( </li><li style="flex:1">)</li></ul>t1 1(light), t1→Wb t11udχ˜0 2 e, µ χ˜0 qs<ul style="display: flex;"><li style="flex:1">˜ ˜ </li><li style="flex:1">˜</li></ul>˜225-525 GeV m( 1)=0 GeV t1 t1(medium), t1→t 1χ˜± χ˜0 χ˜± χ˜0 o<ul style="display: flex;"><li style="flex:1">r</li><li style="flex:1">.</li></ul>neg˜ ˜ <ul style="display: flex;"><li style="flex:1">0</li><li style="flex:1">2 b </li></ul>1 b 2 b 150-580 GeV 200-610 GeV 320-660 GeV t1 t1(medium), t1→b m( 1)<200 GeV, m( 1 )-m( 1)=5 GeV 1pχ˜0 χ˜0 1 e, µ χ˜0 <ul style="display: flex;"><li style="flex:1">˜ ˜ </li><li style="flex:1">˜</li></ul>ÃTLAS-CONF-2013-037 ATLAS-CONF-2013-024 ATLAS-CONF-2013-068 ATLAS-CONF-2013-025 ATLAS-CONF-2013-025 tcm( 1)=0 GeV t1 t1(heavy), t1→t 1χ˜0 ˜ ˜ 0m( 1)=0 GeV χ˜0 et1 t1(heavy), t1→t 1riχ˜0 mono-jet/c-tag ˜˜t1 ˜t1 ˜t2 <ul style="display: flex;"><li style="flex:1">˜ ˜ </li><li style="flex:1">˜</li></ul>090-200 GeV m(t1)-m( 1)<85 GeV t1 tt1, t1→c d1˜ ˜ χ˜0 2 e, µ (Z) 3 e, µ (Z) t1 1(natural GMSB) 500 GeV 271-520 GeV

Pos(EPS-HEP 2013)161 ∗ [email protected] Speaker

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