Background photo: CMS detector in access (i.e., broken-symmetry) mode. David Stuart, UCSB 1

Transcription

1 Recent CMS SUSY Searches David Stuart, UC Santa Barbara Background photo: CMS detector in access (i.e., broken-symmetry) mode David Stuart, UCSB

2 Why supersymmetry? Dark matter and hierarchy problem. Δm H = H H David Stuart, UCSB

3 Why supersymmetry? Naturalness Δm H = H. TeV H.5 TeV. TeV Papucci, et al., arxiv:.696 David Stuart, UCSB

4 Why supersymmetry? Naturalness Δm H = H.5 TeV H.7 TeV. TeV Papucci, et al., arxiv:.696 David Stuart, UCSB

5 Why supersymmetry? Rich signature generator David Stuart, UCSB 5

6 Searches across many signatures with 8 TeV data RPV slepton EWK gauginos sbottom stop squark gluino production g qq χ g bb χ g tt χ g t( t t χ ) ± g qq( χ Wχ ) ± g b( b t( χ Wχ )) q q χ t t χ + t b( χ Wχ ) t t b χ ( χ H G) t ( t t χ ) Z t ( t t χ ) H b b χ b tw χ b bz χ χ χ lll ν χ χ ± χ χ l l ν ν χ χ χ χ Z Z χ χ ± χ χ W Z χ χ χ χ H Z χ χ ± χ χ H W χ χ χ χ llτ ν χ χ ± χ χ τττ ν χ χ ± l l χ g qllν λ g qllν λ g qllν λ 3 33 g qbtµ λ ' 3 g qbtµ λ ' g qqb λ '' 33 3/3 g qqq λ '' g tbs λ '' 33 g qqqq λ '' q qllν λ q qllν λ 3 q qllν λ 33 q qbtµ λ ' 3 q qbtµ λ ' 33 q qqqq λ '' R t µ e ν t λ R t µ τν t λ R 3 t µ τν t λ R 33 t tbtµ λ ' R 33 Summary of CMS SUSY Results* in SMS framework m(mother)-m(lsp)= GeV SUS 3-9 L=9.5 /fb SUS-4- SUS-3-9 L= /fb SUS-3-7 SUS-3-3 L= /fb SUS-3-8 SUS-3-3 L=9.5 /fb SUS-3-3 L=9.5 /fb SUS-3-8 SUS-3-3 L=9.5 /fb SUS-3-9 L=9.5 /fb SUS-4- L=9.5 /fb SUS-3- L=9.5 /fb SUS-3-4 L=9.5 /fb SUS-3-4 SUS-3-4 L=9.5 /fb SUS-3-4 SUS-3-4 L=9.5 /fb SUS-3-8 L=9.4 /fb SUS-3-8 SUS-3-3 L=9.5 /fb SUS-3-8 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-4- L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-4- L=9.5 /fb SUS-4- L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb EXO--49 L=9.5 /fb EXO--49 L=9.5 /fb SUS-3-3 L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS-3-3 L=9.5 /fb x =.5 x =.5 x =.75 x =.95 x =.5 x =.5 x = Mass scales *Observed limits, theory uncertainties not included Only a selection of available mass limits Probe *up to* the quoted mass limit David Stuart, UCSB 6 x =.5 x =.5 x =. x =.5 ICHEP 4 m(lsp)= GeV CMS Preliminary For decays with intermediate mass, = x m +(-x) m m intermediate mother lsp

7 Searches across many signatures with 8 TeV data gluinos squarks stop sbottom EWKinos Sleptons RPV RPV slepton EWK gauginos sbottom stop squark gluino production g qq χ g bb χ g tt χ g t( t t χ ) ± g qq( χ Wχ ) ± g b( b t( χ Wχ )) q q χ t t χ + t b( χ Wχ ) t t b χ ( χ H G) t ( t t χ ) Z t ( t t χ ) H b b χ b tw χ b bz χ χ χ lll ν χ χ ± χ χ l l ν ν χ χ χ χ Z Z χ χ ± χ χ W Z χ χ χ χ H Z χ χ ± χ χ H W χ χ χ χ llτ ν χ χ ± χ χ τττ ν χ χ ± l l χ g qllν λ g qllν λ g qllν λ 3 33 g qbtµ λ ' 3 g qbtµ λ ' g qqb λ '' 33 3/3 g qqq λ '' g tbs λ '' 33 g qqqq λ '' q qllν λ q qllν λ 3 q qllν λ 33 q qbtµ λ ' 3 q qbtµ λ ' 33 q qqqq λ '' R t µ e ν t λ R t µ τν t λ R 3 t µ τν t λ R 33 t tbtµ λ ' R 33 Summary of CMS SUSY Results* in SMS framework m(mother)-m(lsp)= GeV SUS 3-9 L=9.5 /fb SUS-4- SUS-3-9 L= /fb SUS-3-7 SUS-3-3 L= /fb SUS-3-8 SUS-3-3 L=9.5 /fb SUS-3-3 L=9.5 /fb SUS-3-8 SUS-3-3 L=9.5 /fb SUS-3-9 L=9.5 /fb SUS-4- L=9.5 /fb SUS-3- L=9.5 /fb SUS-3-4 L=9.5 /fb SUS-3-4 SUS-3-4 L=9.5 /fb SUS-3-4 SUS-3-4 L=9.5 /fb SUS-3-8 L=9.4 /fb SUS-3-8 SUS-3-3 L=9.5 /fb SUS-3-8 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-4- L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-4- L=9.5 /fb SUS-4- L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS-3-6 L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb EXO--49 L=9.5 /fb EXO--49 L=9.5 /fb SUS-3-3 L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS-3-3 L=9.5 /fb x =.5 x =.5 x =.75 x =.95 x =.5 x =.5 x = Mass scales *Observed limits, theory uncertainties not included Only a selection of available mass limits Probe *up to* the quoted mass limit David Stuart, UCSB 7 x =.5 x =.5 x =. x =.5 ICHEP 4 m(lsp)= GeV CMS Preliminary For decays with intermediate mass, = x m +(-x) m m intermediate mother lsp

8 Searches across many signatures with 8 TeV data RPV slepton EWK gauginos sbottom stop squark gluino production g qq χ SUS 3-9 L=9.5 /fb g bb χ SUS-4- SUS-3-9 L= /fb gluino mass limits g tt χ SUS-3-7 of SUS-3-3. L= /fb TeV g t( t t χ ) SUS-3-8 SUS-3-3 L=9.5 /fb ± g qq( χ Wχ ) SUS-3-3 L=9.5 /fb ± g b( b t( χ Wχ )) SUS-3-8 SUS-3-3 L=9.5 /fb squark mass limits q q χ SUS-3-9 of L=9.5.6 /fb -. TeV t t χ + x =.5 t b( χ Wχ ) SUS-3- L=9.5 /fb x =.5 x =.75 t t b χ ( χ H G) SUS-3-4 L=9.5 /fb stop mass limits t ( t t χ ) Z up SUS-3-4 to SUS L=9.5 TeV, /fb with much model dependence t ( t t χ ) H SUS-3-4 SUS-3-4 L=9.5 /fb b b χ SUS-3-8 L=9.4 /fb sbottom mass b tw limits χ SUS-3-8 up SUS-3-3 to L=9.5.8 /fb TeV b bz χ SUS-3-8 L=9.5 /fb ± χ χ lll ν χ χ SUS-3-6 L=9.5 /fb + x = χ χ l l ν ν χ χ SUS-3-6 L=9.5 /fb χ χ Z Z χ χ SUS-4- L=9.5 /fb ± χ χ W Z χ χ SUS-3-6 L=9.5 EWKinos mass χ χ H Z χ χ limits SUS-4- L=9.5 in /fbsome scenarios ± χ χ H W χ χ SUS-4- L=9.5 /fb ± x =.5 χ χ llτ ν χ χ SUS-3-6 L=9.5 /fb x =.5 x =.95 ± χ χ τττ ν χ χ SUS-3-6 L=9.5 /fb l l χ SUS-3-6 L=9.5 /fb Sleptons mass limits in some scenarios g qllν λ g qllν λ g qllν λ 3 33 g qbtµ λ ' 3 g qbtµ λ ' g qqb λ '' 33 3/3 g qqq λ '' g tbs λ '' 33 g qqqq λ '' q qllν λ q qllν λ 3 q qllν λ 33 q qbtµ λ ' 3 q qbtµ λ ' 33 q qqqq λ '' R t µ e ν t λ R t µ τν t λ R 3 t µ τν t λ R 33 t tbtµ λ ' R 33 Summary of CMS SUSY Results* in SMS framework m(mother)-m(lsp)= GeV SUS-4- L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb EXO--49 L=9.5 /fb EXO--49 L=9.5 /fb SUS-3-3 L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS-3-3 L=9.5 /fb RPV limits in many scenarios x =.5 x =.5 x =. x =.5 ICHEP 4 m(lsp)= GeV CMS Preliminary For decays with intermediate mass, = x m +(-x) m m intermediate Mass scales *Observed limits, theory uncertainties not included Only a selection of available mass limits Probe *up to* the quoted mass limit mother lsp David Stuart, UCSB 8

9 Searches across many signatures with 8 TeV data RPV slepton EWK gauginos sbottom stop squark gluino production g qq χ SUS 3-9 L=9.5 /fb g bb χ SUS-4- SUS-3-9 L= /fb gluino mass limits g tt χ SUS-3-7 of SUS-3-3. L= /fb TeV g t( t t χ ) SUS-3-8 SUS-3-3 L=9.5 /fb ± g qq( χ Wχ ) SUS-3-3 L=9.5 /fb ± g b( b t( χ Wχ )) SUS-3-8 SUS-3-3 L=9.5 /fb squark mass limits q q χ SUS-3-9 of L=9.5.6 /fb -. TeV t t χ + x =.5 t b( χ Wχ ) SUS-3- L=9.5 /fb x =.5 x =.75 t t b χ ( χ H G) SUS-3-4 L=9.5 /fb stop mass limits t ( t t χ ) Z up SUS-3-4 to SUS L=9.5 TeV, /fb with much model dependence t ( t t χ ) H SUS-3-4 SUS-3-4 L=9.5 /fb b b χ SUS-3-8 L=9.4 /fb sbottom mass b tw limits χ SUS-3-8 up SUS-3-3 to L=9.5.8 /fb TeV b bz χ SUS-3-8 L=9.5 /fb ± χ χ lll ν χ χ SUS-3-6 L=9.5 /fb + x = χ χ l l ν ν χ χ SUS-3-6 L=9.5 /fb χ χ Z Z χ χ SUS-4- L=9.5 /fb ± χ χ W Z χ χ SUS-3-6 L=9.5 EWKinos mass χ χ H Z χ χ limits SUS-4- L=9.5 in /fbsome scenarios ± χ χ H W χ χ SUS-4- L=9.5 /fb ± x =.5 χ χ llτ ν χ χ SUS-3-6 L=9.5 /fb x =.5 x =.95 ± χ χ τττ ν χ χ SUS-3-6 L=9.5 /fb l l χ SUS-3-6 L=9.5 /fb Sleptons mass limits in some scenarios g qllν λ g qllν λ g qllν λ 3 33 g qbtµ λ ' 3 g qbtµ λ ' g qqb λ '' 33 3/3 g qqq λ '' g tbs λ '' 33 g qqqq λ '' q qllν λ q qllν λ 3 q qllν λ 33 q qbtµ λ ' 3 q qbtµ λ ' 33 q qqqq λ '' R t µ e ν t λ R t µ τν t λ R 3 t µ τν t λ R 33 t tbtµ λ ' R 33 Summary of CMS SUSY Results* in SMS framework m(mother)-m(lsp)= GeV SUS-4- L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb EXO--49 L=9.5 /fb EXO--49 L=9.5 /fb SUS-3-3 L=9.5 /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS--7 L=9. /fb SUS-3-3 L= /fb SUS-3-3 L=9.5 /fb RPV limits in many scenarios And a few modest discrepancies x =.5 x =.5 x =. x =.5 ICHEP 4 m(lsp)= GeV CMS Preliminary For decays with intermediate mass, = x m +(-x) m m intermediate Mass scales *Observed limits, theory uncertainties not included Only a selection of available mass limits Probe *up to* the quoted mass limit mother lsp David Stuart, UCSB 9

10 Large increase in cross-sections at 3 TeV wrt 8 TeV Backgrounds increase by or 3 Stop and gluino cross-sections increase by 8-4. David Stuart, UCSB

11 Potentially large yields despite small luminosity With fb - would produce - events for.5 TeV gluinos.8 TeV squarks 9 GeV stops Sensitivity increase of O() GeV wrt Run M.Krämer & M.Muhlleitner, arxiv: David Stuart, UCSB

12 Outline. Overview of strategy. Inclusive search in all-hadronic mode broad coverage 3. Gluino to top stop search in single lepton mode new methodology 4. Dilepton search, on Z or kinematic edge followup Run deviation David Stuart, UCSB

13 Strategy Search broadly in tails of kinematics and multiplicity. Optimized for the unknown. Search for specific production and decay modes. Optimized for specific scenarios. Background (SM) modeling well validated in the bulk, but unknown for the tails. Backgrounds typically from ttbar, W, and Z plus many jets and/or high pt. Signal would be a few orders of magnitude out on those tails. So measure tails in situ with minimal reliance on MC modeling. David Stuart, UCSB 3

14 Inclusive search targeting high multiplicity, energy, and/or MET. t b P g t P g b t χ χ P t g t t χ P g b b χ David Stuart, UCSB 4

15 Inclusive search targeting high multiplicity, energy, and/or MET. MET HT = sum pt(jets) SM backgrounds are dominantly: QCD multijet ttbar W+jets Z+jets Rare SM processes, e.g., ttz NJ & Nb Suppress them with combinations of these variables, so bin across them. Challenge is then all about predicting the backgrounds. David Stuart, UCSB 5

16 Inclusive search targeting high multiplicity, energy, and/or MET. MT MET HT = sum pt(jets) SM backgrounds are dominantly: QCD multijet ttbar W+jets Z+jets Rare SM processes, e.g., ttz NJ & Nb Suppress them with combinations of these variables, so bin across them. Challenge is then all about predicting the backgrounds. David Stuart, UCSB 6

17 QCD multijet background is difficult to predict. So hit it hard. Standard cuts, but keep MET cut small with MT. Cluster jets into two hemispheres, J and J, and calculate Events / 5 GeV 8 H T > GeV miss E > 3 GeV 7 T j, b CMS Simulation Multijet Top quark W+jets Z νν pp g g, g bbχ m g = GeV m = GeV χ -.3 fb (3 TeV) M T David Stuart, UCSB 7

18 QCD multijet background is difficult to predict. So hit it hard. Standard cuts, but keep MET cut small with MT. Cluster jets into two hemispheres, J and J, and calculate Extreme H T High H T Medium H T Low H T Events / 5 GeV 8 H T > GeV miss E > 3 GeV 7 T j, b CMS Simulation Multijet Top quark W+jets Z νν pp g g, g bbχ m g = GeV m = GeV χ -.3 fb (3 TeV) Very low H T QCD multijet ends up being negligible, after a messy prediction. David Stuart, UCSB 8 M T

19 A few background processes, with mix varying across tails Main backgrounds are: Z invisible + jets Top or W + jets with missed leptons Neither has reliable MC modeling for kinematics (HT,Nj,Nb), but do trust decay BR and lepton efficiency. N b (p T > GeV) 3 CMS Supplementary (Simulation) arxiv: Multijet Top quark W+jets Z N j (p T > 3 GeV) (3 TeV) H T [575, ] GeV David Stuart, UCSB 9

20 A few background processes, with unreliable modeling Main backgrounds are: Z invisible + jets Top or W + jets with missed leptons Events / 5 GeV CMS Supplementary H T > GeV MET > GeV ( j, b) > GeV ( j, b ) M T arxiv: Data W+jets Top quark Multijet -.3 fb (3 TeV) Neither has reliable MC modeling for kinematics (HT,Nj,Nb), but do trust decay BR and lepton efficiency. Data/MC H T David Stuart, UCSB

21 A few background processes, with unreliable modeling Main backgrounds are: Z invisible + jets Top or W + jets with lost leptons Neither has reliable MC modeling for kinematics (HT,Nj,Nb), but do trust decay BR and lepton efficiency. Events Data/MC H T > GeV MET > GeV ( j, b) 5 M T > GeV ( j, b ).5.5 CMS Supplementary arxiv: Data W+jets Top quark Multijet -.3 fb (3 TeV) N(jets) David Stuart, UCSB

22 A few background processes, with unreliable modeling Main backgrounds are: Z invisible + jets Top or W + jets with lost leptons Neither has reliable MC modeling for kinematics (HT,Nj,Nb), but do trust decay BR and lepton efficiency. Events Data/MC CMS Supplementary j, lepton > GeV M T arxiv: Data Top quark W+jets Multijet -.3 fb (3 TeV) N(b jets) David Stuart, UCSB

23 Top and W+jets background from lost-leptons Prediction for lost lepton contribution each MT bin is Normalize per kinematic bin (MT< to suppress signal contamination). Lepton efficiency (including taus) Extrapolation of MT shape bins in Nj and Nb: -3j * (b, b, b) 4-6j * (b, b, b) -6j * 3b 7j * (b, b, b, 3b) For each Nj and Nb bin David Stuart, UCSB 3

24 Uncertainty on background from MT extrapolation Events / Bin Vary the usual MC parameters: (PDF, renorm/factrz, W/top) Check MT shape in -lepton data Total MT shape uncertainty reaches 4% in highest bins Statistical uncertainty from -lepton CR reaches % CMS j, b, lepton > GeV M T Data Top quark W+jets Multijet -.3 fb (3 TeV) Events / Bin 3 CMS j, b, lepton > GeV M T Data Top quark W+jets Multijet -.3 fb (3 TeV) Data/MC M T Data/MC M T David Stuart, UCSB 4

25 Z νν background measured with a γ+jets control sample. q Z ν ν q Z ν ν j j j j j j g j g j pt(γ)>8 MT> GeV David Stuart, UCSB 5

26 Z νν background measured with a γ+jets control sample. Photon purity CMS fb (3 TeV) ) / γ ratio - l + Z(l CMS...8 Data Simulation -.3 fb (3 TeV) Data (fit) j, b MC purity (photon removed) H T Data / MC H T David Stuart, UCSB 6

27 Z νν background uncertainty determined similarly to W/top Compare also to MT distribution in a -lepton W sample. Fraction / Bin CMS -.3 fb (3 TeV) 575 < H T < GeV Z νν (MC) γ estimate (Data) W estimate (Data) Fraction / Bin CMS -.3 fb (3 TeV) < H T < 5 GeV Z νν (MC) γ estimate (Data) W estimate (Data) 3 3 Ratio to Z M T Ratio to Z M T David Stuart, UCSB 7

28 Results integrated over MT CMS -.3 fb (3 TeV) Entries b Jet H [,45] GeV b T H T [45,575] GeV H T [575,] GeV Pre-fit background H T [,5] GeV H T > 5 GeV Data Multijet Lost lepton Z νν Data/Est. 3 [,5] [5,35] [35,45] [45,575] [575,7] [7,] > [,5] [5,35] [35,45] [45,575] >575-3j, b -3j, b -3j, b 4-6j, b 4-6j, b 4-6j, b 7j, b 7j, b 7j, b -6j, 3b 7j, 3b -3j, b -3j, b -3j, b 4-6j, b 4-6j, b 4-6j, b 7j, b 7j, b 7j, b -6j, 3b 7j, 3b -3j, b -3j, b -3j, b 4-6j, b 4-6j, b 4-6j, b 7j, b 7j, b 7j, b -6j, 3b 7j, 3b -3j, b -3j, b -3j, b 4-6j, b 4-6j, b 4-6j, b 7j, b 7j, b 7j, b -6j, 3b 7j, 3b -3j, b -3j, b -3j, b 4-6j, b 4-6j, b 4-6j, b 7j, b 7j, b 7j, b -6j, 3b 7j, 3b David Stuart, UCSB 8

29 Results for sample HT bin CMS -.3 fb (3 TeV) Entries Pre-fit background [575, ] GeV -3j b -3j b -3j b 4-6j b 4-6j b 4-6j b 7j b H T 7j b 7j b Data Multijet Lost lepton Z νν -6j 3b 7j 3b Data/Est. 3 [,3] [3,4] [4,6] [6,8] >8 [,3] [3,4] [4,6] [6,8] >8 [,3] [3,4] [4,6] >6 [,3] [3,4] [4,6] [6,8] >8 [,3] [3,4] [4,6] >6 [,3] [3,4] [4,6] >6 [,3] [3,4] >4 [,3] [3,4] >4 [,3] [3,4] >4 [,3] [3,4] >4 [,3] [3,4] >4 David Stuart, UCSB 9

30 Results for nd highest HT bin CMS -.3 fb (3 TeV) Entries Pre-fit background -3j b -3j b -3j b H T [, 5] GeV 4-6j b 4-6j b 4-6j b 7j b 7j b Data Multijet Lost lepton Z νν 7j b -6j 3b 7j 3b Data/Est. 3 [,4] [4,6] [6,8] [8,] > [,4] [4,6] [6,8] >8 [,4] >4 [,4] [4,6] [6,8] [8,] > [,4] [4,6] [6,8] >8 [,4] [4,6] >6 [,4] [4,6] >6 [,4] [4,6] >6 [,4] >4 [,4] >4 [,4] >4 David Stuart, UCSB 3

31 Results for highest HT bin CMS -.3 fb (3 TeV) Entries Pre-fit background -3j b -3j b -3j b H T > 5 GeV 4-6j b 4-6j b 4-6j b 7j b 7j b Data Multijet Lost lepton Z νν 7j b -6j 3b 7j 3b Data/Est. 3 [,4] [4,6] [6,8] [8,] > [,4] [4,6] >6 > [,4] [4,6] [6,8] [8,] > [,4] [4,6] >6 [,4] [4,6] >6 [,4] >4 [,4] >4 [,4] >4 > > David Stuart, UCSB 3

32 Limits: global fit to signal strength across all 7 bins CMS -.3 fb (3 TeV) Entries Post-fit background -3j b -3j b -3j b H T > 5 GeV 4-6j b 4-6j b 4-6j b 7j b Data Multijet Lost lepton Z νν pp g g, g bb χ m g =5 GeV = GeV m χ 7j b 7j b -6j 3b 7j 3b 3 [,4] [4,6] [6,8] [8,] > [,4] [4,6] >6 > [,4] [4,6] [6,8] [8,] > [,4] [4,6] >6 [,4] [4,6] >6 [,4] >4 [,4] >4 [,4] >4 > > David Stuart, UCSB 3

33 Squark limits q q P q χ P g q χ χ m P CMS pp q q, q q χ one light q David Stuart, UCSB q + q L -.3 fb Observed ± σ theory Expected ± σ experiment NLO+NLL exclusion ( u, R q d, s, c) (3 TeV) m q q χ 3 95% CL upper limit on cross section [pb] χ m CMS P pp g g, g q q χ Observed ± σ theory Expected ±, σ -.3 fb (3 TeV) NLO+NLL exclusion experiment g m g q q χ 3 95% CL upper limit on cross section [pb] 33

34 Sbottom limits b b P b χ P g b χ χ m P CMS David Stuart, UCSB -.3 fb (3 TeV) 7 pp b b, b b χ NLO+NLL exclusion 6 Observed ± σ theory Expected ± σ experiment b m b b χ 3 95% CL upper limit on cross section [pb] χ m CMS P pp g g, g b b χ -.3 fb Observed ± σ theory Expected ± σ experiment (3 TeV) NLO+NLL exclusion g m g b b χ 3 95% CL upper limit on cross section [pb] 34

35 Stop limits t t P t χ P g t χ χ m P CMS David Stuart, UCSB m t = m t χ + m -.3 fb pp t t, t t χ NLO+NLL exclusion Observed ± σ theory Expected ± σ experiment t m t t χ (3 TeV) 3 95% CL upper limit on cross section [pb] χ m CMS P pp g g, g t t χ -.3 fb Observed ± σ theory Expected ± σ experiment (3 TeV) NLO+NLL exclusion g m g t t χ 3 95% CL upper limit on cross section [pb] 35

36 Stop limits t SUS-5-3, arxiv:63:453 t P t χ P g t χ χ m P CMS David Stuart, UCSB m t = m t χ + m -.3 fb pp t t, t t χ NLO+NLL exclusion Observed ± σ theory Expected ± σ experiment t m t t χ (3 TeV) 3 95% CL upper limit on cross section [pb] χ m CMS P pp g g, g t t χ -.3 fb Observed ± σ theory Expected ± σ experiment * * * * 8 TeV * limits * (3 TeV) NLO+NLL exclusion g m g t t χ 3 95% CL upper limit on cross section [pb] 36

37 Search using MHT rather than MT. Background prediction similar. CMS -.3 fb (3 TeV) Events N jet 6 7 N jet 8 N jet 9 N b-jet 3 Data Lost lepton Hadronic τ lepton Z νν QCD miss H T HT-MHT bins Bin 6 Bin 4 Bin 5 (Obs.-Exp.) Exp Search region bin number Bin Bin Bin H T Other inclusive all-hadronic searches using other variables: alphat and razor. Also performed with many bins. David Stuart, UCSB 37

38 Search in the single lepton mode targeting gluino to top + stop P g t t t χ P g t t χ GeV isolated e/µ in gluino decays with 4 W ± t l mode: higher purity with small BR cost David Stuart, UCSB 38

39 Search in the single lepton mode targeting gluino to top + stop Baseline selection: One e/µ, pt > HT > 5 MET > njets 6, nb Leaves a single background process mt>4 leaves lost dilepton top David Stuart, UCSB Events/(35 GeV) Data / MC CMS Preliminary L =. fb (3 TeV) Data g g, g tt χ (5,) g g, g tt χ (,8) tt, true lepton tt, true leptons ` t t - W+jets Single top ttv Other ` t t 4 6 mt m T 39

40 Search in the single lepton mode targeting gluino to top + stop Challenge is predicting the lost dilepton background at high m T for all kinematic regions (MET, n b, n j ) Predict dilepton background using single lepton events Using an event wide kinematic property that is the same for l and l events but differs for signal. David Stuart, UCSB 4

41 MJ = the sum of masses of fat jets (R=.) Larger for gluino decays due to boosted hadronic tops and accidental boost when partons randomly overlap. Di-lepton ttbar g! t t leptonic top m(j) GeV ISR jet m(j) GeV leptonic top m(j) GeV light jets b-jets leptonic top m(j) GeV Two hadronic tops m(j) mtop hadronic top m(j) mtop lepton David Stuart, UCSB 4

42 MJ = the sum of masses of fat jets (R=.) Larger for gluino decays due to boosted hadronic tops and accidental boost when partons randomly overlap. Cluster R=.4 jets and leptons into R=. jets with anti-kt algorithm. Naturally incorporates jet corrections. David Stuart, UCSB 4

43 MJ = the sum of masses of fat jets (R=.) Larger for gluino decays due to boosted hadronic tops and accidental boost when partons randomly overlap. Cluster R=.4 jets and leptons into R=. jets with anti-kt algorithm. Naturally incorporates jet corrections. MJ first suggested in pheno papers by Wacker, Cohen, and others, e.g., PRD 85,559 & JHEP3(3)6. First used in multijet search by ATLAS in e.g., PRD 9,6 Useful discussion with Ariel Schwartzman re: AK4 reclustering. David Stuart, UCSB 43

44 MJ = the sum of masses of fat jets (R=.) More sophisticated methods improve resolution for individual masses, but that is not the goal here. David Stuart, UCSB 44

45 An example event David Stuart, UCSB 45

46 An example event pt=468 GeV MET=373 GeV b-tag electron pt=7 GeV b-tag David Stuart, UCSB 46

47 An example event mj=54 GeV skinny jets pt=468 GeV mj= GeV skinny jet MET=373 GeV b-tag mj=897 GeV 6 skinny jets electron pt=7 GeV b-tag David Stuart, UCSB 47

48 MJ = the sum of masses of fat jets (R=.) Use an event wide kinematic property that is the same for l and l events but differs for signal. Top decay products have cutoff at *m(top), lower for l than for l. Random overlap of ISR jets dominates for high pt events, with similar shape for l and l. % events/(4 GeV) CMS Simulation gg, g tt χ (5,) tt, true lepton tt, true leptons ISR p T < GeV 3 TeV M J David Stuart, UCSB 48

49 MJ = the sum of masses of fat jets (R=.) Use an event wide kinematic property that is the same for l and l events but differs for signal. Top decay products have cutoff at *m(top), lower for l than for l. Random overlap of ISR jets dominates for high pt events, with similar shape for l and l. % events/(4 GeV) CMS Simulation gg, g tt χ (5,) tt, true lepton tt, true leptons ISR p T < GeV 3 TeV % events/(4 GeV) CMS Simulation gg, g tt χ (5,) tt, true lepton tt, true leptons ISR p T > GeV 3 TeV M J David Stuart, UCSB M J 49

50 Measure mt shape at low MJ and normalize at high MJ Bkgnd predicted as m T t t (l), ρ=.5 t t (l), ρ=.3 g g, g tt χ (5,) CMS Simulation R3 3 TeV R4 R(m T ) = NR3/NR R(MJ) = NR/NR 5 with MC correction factor of R M J R Expect R(m T ) and R(M J ) to have small correlations, κ is their (double) ratio, insensitive to mis-modeling. David Stuart, UCSB 5

51 Measure mt shape at low MJ and normalize at high MJ Bkgnd predicted as R(m T ) = NR3/NR R(MJ) = NR/NR % events/(5 GeV) CMS Simulation tt, true lepton: m 4 GeV T tt, true leptons: m > 4 GeV T 3 TeV with MC correction factor of David Stuart, UCSB / Low m T High m T.5..5 Expect R(m T ) and R(M J ) to have small correlations, 5 5 κ is their (double) ratio, insensitive to mis-modeling. M J 5

52 Additional discrimination with nj, nb, and MET binning L =.3 fb Other QCD ttv Single t W+jets tt (`) tt (`) SM bkg. Ttttt(NC) No selection 3.3 `, p T > GeV.9 H T > 5 GeV ET miss > GeV N jets 6, p T > 3 GeV N b M J > 5 GeV m T > 4 GeV M J > 4 GeV N b ET miss > 4 GeV N jets 9, p T > 3 GeV Need to predict signal region (R4 = high m T & high M J ) for each n j, n b, MET bin. Signal David Stuart, UCSB 5

53 Additional discrimination with nj, nb, and MET binning.5. CMS Simulation N b N b N b = = 3 M 4 GeV > 4 GeV J M J 3 TeV R(m T ).5..5 Baseline selection Baseline selection MC predicts that R(m T ) and R(M J ) are at most weakly dependent on n j and n b, O(%) for n j >5. N jets David Stuart, UCSB 53

54 Background prediction with nj, nb, and MET binning mt MJ David Stuart, UCSB 54

55 MC correction factors for each nj, nb, and MET binning CMS Simulation N b = N b = N 3 b N b 3 TeV.5 κ.5 miss T miss T miss T miss E T E 4 E > 4 E 4 > N jets N jets - % corrections David Stuart, UCSB 55

56 Systematic uncertainties Validate the background estimation method using ttbar events with two reconstructed leptons Replace R3 & R4 (mostly dilepton ttbar with a lost lepton) by D3 & D4 which have two reconstructed leptons. ( D for dilepton). In D3 and D4: Require MET<4 GeV and n b to reduce signal contamination. Shift n jets requirement down by to have same number of objects in fat jet clustering. David Stuart, UCSB 56

57 Systematic uncertainties M J shapes consistent for R & R vs D3 & D4 Observed dilepton yields consistent with prediction Use precision of test as systematic uncertainty David Stuart, UCSB 57

58 Systematic uncertainties Validate the background estimation method using ttbar events with two reconstructed leptons Other smaller uncertainties determined by MC variation. Source Fractional uncertainty [%] Data sample size 8 8 Dilepton control sample test Simulation sample size 5 7 Jet energy resolution Jet energy corrections 5 ISR p T 5 Top p T 4 Non-tt background David Stuart, UCSB 58

59 Results nb= nj 6 MET Predict 6.6±.5 Observe 8 David Stuart, UCSB 59

60 Results nb nj 6 MET Predict 5.6±.8 Observe David Stuart, UCSB m T Data g g, g tt χ (5,) - CMS.3 fb (3 TeV) M J ) Simulated events/(8 GeV 6

61 Results Region: bin k Ttttt(NC) Ttttt(C) Fitted µ bkg (PF) Fitted µ bkg (GF) Obs. < ET miss apple 4 GeV R: all N jets, N b ± ± R: 6 apple N jets apple 8, N b = ± ± R: N jets 9, N b = ± ±.7 7 R: 6 apple N jets apple 8, N b = ± ± 6. 4 R: N jets 9, N b = ± ±.5 7 R: 6 apple N jets apple 8, N b 3... ± 3.5. ± 3. R: N jets 9, N b ±..9 ±.9 R3: all N jets, N b ± ± 4. R4: 6 apple N jets apple 8, N b =. ±.9 ± ± ±. 6 R4: N jets 9, N b =.9 ±.6 ± ±.3.4 ±. R4: 6 apple N jets apple 8, N b =. ±.6 ± ±..9 ±.8 R4: N jets 9, N b =.5 ±. ± ±.3.4 ±. R4: 6 apple N jets apple 8, N b 3.5 ±. ± ±.4.9 ±.3 R4: N jets 9, N b 3.5 ±. ± ±.. ±. ET miss > 4 GeV R: all N jets, N b ± ± 4. 6 R: 6 apple N jets apple 8, N b =.. 8. ± ±.5 8 R: N jets 9, N b =... ±..7 ±. R: 6 apple N jets apple 8, N b ±.7.5 ±.4 3 R: N jets 9, N b.4.6. ±..9 ±.9 R3: all N jets, N b ±..9 ±.4 4 R4: 6 apple N jets apple 8, N b =.9 ±.6 ± ±.7. ±.7 R4: N jets 9, N b =.98 ±.6 ± ±.3.3 ±. R4: 6 apple N jets apple 8, N b.9 ±. ± ±.8.5 ±.4 R4: N jets 9, N b.9 ±.4 ± ±.3. ±. David Stuart, UCSB 6

62 Limits P P P P g g g g t t t t t t t t χ χ t t χ χ χ m CMS pp g g, g t t χ -.3 fb Observed ± σ theory Expected ± σ experiment (3 TeV) NLO+NLL exclusion m g 3 95% CL upper limit on cross section [pb] David Stuart, UCSB 6

63 Limits t - CMS.3 fb (3 TeV) P g t t χ χ m SUS-5-7, arxiv:65:468 pp pp g g, g t t χ g g+ t g, t t, t t t χ (m t Observed - m χ = 75 GeV) Expected P g t t χ 8 t 6 T5ttttDM75: an extreme scenario 4 m gluino m stop m LSP 75 GeV David Stuart, UCSB 63 m g Compressed stop decay degrades kinematic efficiency. For mlsp, LSP s have no momentum so only lost dilepton signal events pass MET & mt selection.

64 Opposite sign dilepton search b l + b b χ χ l Z ( ) b f l χ χ f I. Hinchliffe, F.E. Paige, M.D. Shapiro, J. Söderqvist, and W. Yao, PRD.55.55, 997 David Stuart, UCSB 64

65 Opposite sign dilepton search MET (5) & nj 3() Events / 5 GeV CMS 9.4 fb (8 TeV) Data Fit FS DY Signal SF central leptons Flavor symmetric background Efficiencies measured in high stats Z ee & µµ samples 4 Pull m ll m ll David Stuart, UCSB 65

66 Opposite sign dilepton search MET (5) & nj 3() Events / 5 GeV CMS fb (8 TeV) Data Fit OF central leptons Flavor symmetric background Efficiencies measured in high stats Z ee & µµ samples 4 Pull m ll m ll David Stuart, UCSB 66

67 Opposite sign dilepton search MET (5) & nj 3() Events / 5 GeV Pull CMS 9.4 fb (8 TeV) Data Fit FS DY Signal SF central leptons m ll Flavor symmetric background Efficiencies measured in high stats Z ee & µµ samples Drell-Yan like background MET templates from γ+jets - - j j j j m ll j j g g David Stuart, UCSB 67 q Z j ν ν q Z j ν ν

68 Opposite sign dilepton search MET (5) & nj 3() Events / 5 GeV CMS 9.4 fb (8 TeV) Data Fit FS DY Signal SF central leptons m ll Excess in < m < 7 73 ± 4 predicted vs 86 observed.6 σ (local) deviation Pull m ll David Stuart, UCSB 68

69 Opposite sign dilepton search: identical 3 TeV repeat Events / GeV CMS Preliminary Central signal region Data -. fb (3 TeV) Total backgrounds Drell--Yan Total uncert. 5 Data / Bgnd.5.5 David Stuart, UCSB Systematic uncert. m ll 69

70 Opposite sign dilepton search: identical 3 TeV repeat Events / GeV Data / Bgnd CMS Preliminary David Stuart, UCSB Central signal region Data Total backgrounds Drell--Yan Total uncert. Scaled 8 TeV signal fit: -. fb (3 TeV) = 3 GeV hypothesis Systematic uncert. m b m b m b = 5 GeV hypothesis = 7 GeV hypothesis m ll 8 TeV excess not confirmed. Red distributions model shape and scaled size of 8 TeV excess for three different sbottom mass hypotheses. 7

71 Opposite sign dilepton search, on-z Events /.5 GeV Njets, MET > 5 GeV HT+pT+pT > 6 GeV, On-Z: 8 < mll < GeV min(δφmet, j, ΔΦMET, j) >.4 4 ATLAS 8 - s = 8 TeV,.3 fb SR-Z ee Data Standard Model Flavour Symmetric Other Backgrounds m( g),µ=(7,)gev m( g),µ=(9,6)gev Events /.5 GeV ATLAS - s = 8 TeV,.3 fb 8 9 events observed with BG of.6 ± 3. 3σ SR-Z µµ EPJC 75 (5) 38 Data Standard Model Flavour Symmetric Other Backgrounds m( g),µ=(7,)gev m( g),µ=(9,6)gev David Stuart, UCSB m ll m ll 7

72 Opposite sign dilepton search, on-z Njets, MET > 5 GeV HT+pT+pT > 6 GeV, On-Z: 8 < mll < GeV min(δφmet, j, ΔΦMET, j) >.4 observed.3 ±. BG..σ ATLAS-CONF-5-8 David Stuart, UCSB 7

73 Opposite sign dilepton search, on-z Njets, MET > 5 GeV HT+pT+pT > 6 GeV, On-Z: 8 < mll < GeV min(δφmet, j, ΔΦMET, j) >.4 Events/5 GeV 3 data MET Templates FS background Other SM CMS Preliminary Σ p T (lep φ(e, miss T -. fb (3 TeV) )+ H T, (jet > 6 GeV )) >.4, N jets observed.3 ±. BG..σ obs ATLAS-CONF miss David Stuart, UCSB E T GeV 73 Data Prediction.5.5 CMS-SUS-5- ± 3 BG

74 6 running 7RtDl IntHJUDtHd LumLnRsLty (pb ) David Stuart, UCSB C6,ntegrated LumLnoVLty, SS, 6, p s = 3 TeV DDtD included fuop 6-4- :48 to 6-6- :6 8TC PUeliPinDUy LHC DHlLvHUHd: 736. pb C6 5HcRUdHd: 59. pb 3 ASU 6 ASU 9 ASU Dy 5 Dy 8 Dy Dy 4 Dy 7 Dy Dy 3 Dy 6 Dy 9 Dy Jun DDtH (87C)

75 6 running fb - fb - 3 fb - David Stuart, UCSB 75

76 Conclusion: Not yet, but not done. Recent CMS SUSY searches, David Stuart, UCSB 76

77 Conclusion: Not yet, but not done. 3 TeV 3 TeV 7 TeV 8 TeV Recent CMS SUSY searches, David Stuart, UCSB 77

78 Conclusion: Not yet, but not done. 3 TeV 3 TeV 7 TeV 8 TeV Recent CMS SUSY searches, David Stuart, UCSB 78

79 Acknowledgements Funded by: and Citation for multimedia used: and references therein.