) = 0 GeV. Preliminary. Combined. CL s observed 95% C.L. limit. CL s median expected limit ATLAS EPS L dt = 4.71 fb, = 1 fb.

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5 squark mass [GeV] Squark-gluino-neutralino model, m(χ 0 ) = 0 GeV 1 ATLAS Combined Preliminary CL s observed 95% C.L. limit CL s median expected limit Expected limit ±1 σ ATLAS EPS L dt = 4.71 fb, σ SUSY σ SUSY s=7 TeV = 1 fb = 10 fb 800 σ SUSY = 100 fb gluino mass [GeV]

6 Figure 7: 95% CL exclusion limits obtained by using the signal region squark mass [GeV] Squark-gluino-neutralino model, m(χ 0 ) = 0 GeV 1 ATLAS Combined Preliminary CL s observed 95% C.L. limit CL s median expected limit Expected limit ±1 σ ATLAS EPS L dt = 4.71 fb, σ SUSY s=7 TeV = 1 fb σ SUSY = 10 fb 800 σ SUSY = 100 fb gluino mass [GeV]

7 squark mass [GeV] Squark-gluino-neutralino model, m(χ 0 ) = 0 GeV ATLAS Preliminary Combined observed 95% C.L. limit CL s median expected limit CL s Expected limit ±1 σ ATLAS EPS L dt = 4.71 fb, s=7 TeV σ SUSY = 1 fb = 10 fb σ SUSY = 100 fb σ SUSY gluino mass [GeV] Figure 7: 95% CL s exclusion limits obtained by using the signal region with the best expected sensitivity at each point in a simplified MSSM scenario with only strong production of gluinos and first- and second-generation squarks, and direct decays to jets and neutralinos (left); and in the (m 0 ; m 1/2 ) plane of MSUGRA/CMSSM for tan = 10, A 0 = 0 and µ>0 (right). The red lines show the observed limits, the dashed-blue lines the median expected limits, and the dotted blue lines the ±1 variation on the expected limits. ATLAS EPS 2011 limits are from [17] and LEP results from [59]. 7 Summary This note reports a search for new physics in final states containing high-p T jets, missing transverse momentum and no electrons or muons, based on the full dataset (4.7 fb 1 ) recorded by the ATLAS experiment at the LHC in Good agreement is seen between the numbers of events observed in the data and the numbers of events expected from SM processes. The results are interpreted in both a simplified model containing only squarks of the first two generations, a gluino octet and a massless neutralino, as well as in MSUGRA/CMSSM models with tan = 10, A 0 = 0 and µ>0. In the simplified model, gluino masses below 940 GeV and squark masses below 1380 GeV are excluded at the 95% confidence level. In the MSUGRA/CMSSM models, values of m 1/2 < 300 GeV are excluded for all values of m 0, and m 1/2 < 680 GeV for low m 0. Equal mass squarks and gluinos are excluded below 1400 GeV in both scenarios. References [1] L. Evans and P. Bryant, LHC Machine, JINST 3 (2008) S [2] H. Miyazawa, Baryon Number Changing Currents, Prog. Theor. Phys. 36 (6) (1966) [3] P. Ramond, Dual Theory for Free Fermions, Phys. Rev. D3 (1971) [4] Y. A. Golfand and E. P. Likhtman, Extension of the Algebra of Poincare Group Generators and Violation of p Invariance, JETP Lett. 13 (1971) [Pisma Zh.Eksp.Teor.Fiz.13: ,1971]. [5] A. Neveu and J. H. Schwarz, Factorizable dual model of pions, Nucl. Phys. B31 (1971)

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10 W α = θ α D d 2 θ 2 W α W α j A j M L m D λ j ã j α m D = D /M.

11 8 < : A j j =1...8 A j j =1...3 A j j =1

12 d 4 θ (W α W α ) W β W β M 6 Q Q. Z d m 4 D M 2 Q Q

13 M 2 f = i C i (f) i M 2 i log m2 i M 2 i

14 M 2 f = i C i (f) i M 2 i log m2 i M 2 i

15 ãj A j = a j d 2 θ 2 W α W j αa j L m 2 M D (a j + a j )2 d 2 θ W αw α M 2 A 2 j.

16 M 2 f = i C i (f) i M 2 i log m2 i M 2 i 2 M 2 q (700 GeV) 2 M 3 log r 3 5 TeV log M 2 q ' (760 GeV) 2 M3 log r 3 3TeV log 4

17 m 2 H u = 3 2 t 8 2 M 2 t log 2 M 2 t m 2 H u = 2 t 2 2 s M 3 2 log 2 M m 2 H u MSSM M3 4 2 log / M 3 3 2

18 m 2 H u = 3 2 t 8 2 M 2 t log 2 M 2 t m 2 H u = 2 t 2 2 s M 3 2 log 2 M m 2 H u = 3 2 t 8 2 M 2 t log m2 3 M 2 t M 2 q (700 GeV) 2 M 3 5 TeV 2 log r 3 log 1.5 log M 2 3 M 2 t ' log 3 4 s m 2 H u MSSM M3 4 2 log / M m 2 H u SSSM M log r 3 log 1.5

19 d 2 θ 2 W α W α j A j M L m D λ j ã j 2m D (a j + a j)d j D j ( i g k q i t j q i ) 1 2 D2 j m 2 h = m 2 Z cos cos2 y 2 t m 2 t ln m t 1 m t 2 m 2 t

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21 impact on groups. the Higgs Thispotential. choice of Second, R-partners while ensures the real that electroweak symmetry breaking by the Higgs fields ) H u,d parts of A a acquire a mass O(M D ) from Eq. (2), Im(A a masses are larger real. than The 1 TeV full components couple offrom remains massless at this level. B and the re does not spontaneously break R-symmetry. The MRSSM in Eq. (A5). the electroweak Soft-breakin ph In order also to defines enforce R-symmetry the R-charges onof the the superpotential, matter fields to be the Higgs R[Q sector i,u tween the Higgs and squ i c,dc of the i,l i,e MRSSM c the MRSSM, on th i ] = 1, must allowing be enlarged. the usual Yukawa The couplings the MSSM in the superpotential. is replaced by the R-symmetric µ- by R-symmetry. we take tofor beviab clos µ-term of relative size Furthermore, of supersy h terms Given the extra matter content, there are new superpotential operators [35] one can write in the R-symmetric one to be within roughly the MRSSM theory, Throughout this paper W µ u H u R u + µ d R d H d, (3) ino masses to be large. T where R u,d are W new, R-charge u lations and is motivated b B B H u R R[R u + d B u,d ] = B R 2 d fields H d that 1 R-symmetry is not to avoid conflict with pre transform as (1, 2) 1/2 + under u W a W Hthe u standard a R u + d Wmodel a W R d gauge a H d. (4) be avoided as long Ref. [35] found the SU(2 groups. This choice of R-partners ensures that electroweak symmetry breaking by the Higgs fields H larger than 1 TeV. Such h u,d couple 2 from the rest of th does not spontaneously break R-symmetry. The MRSSM the electroweak phase tra also defines the R-charges of the matter fields to be R[Q i,ui c,dc i,l i,ei c the MRSSM, on the other ] = 1, allowing the usual Yukawa couplings in1the superpotential. we take to be closer to th M 125 Given the extra matter content, there 2 are =1TeV Furthermore, heavy D new superpotential µ W with the MRSSM Higgs 0 operators [35] one can write in the u = R-symmetric µ d = 200 GeV theory, B W u B B H u R u + d 50 B B R d H d m( t L,R )=3TeV + u W a W H u a R u + d W a W R d a H d. (4) 1 R-symmetry is not essential be avoided as long as X is n

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26 Squark masses at which the cross-section of the final stat

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32 squark mass [GeV] Squark-gluino-neutralino model, m(χ 0 ) = 0 GeV 1 ATLAS Preliminary Combined observed 95% C.L. limit CL s median expected limit CL s Expected limit ±1 σ ATLAS EPS L dt = 4.71 fb, s=7 TeV σ SUSY = 1 fb = 10 fb σ SUSY = 100 fb σ SUSY gluino mass [GeV] Figure 7: 95% CL s exclusion limits obtained by using the signal region with the best expected sensitivity at each point in a simplified MSSM scenario with only strong production of gluinos and first- and second-generation squarks, and direct decays to jets and neutralinos (left); and in the (m 0 ; m 1/2 ) plane of MSUGRA/CMSSM for tan = 10, A 0 = 0 and µ>0 (right). The red lines show the observed limits, the q dashed-blue lines the median expected limits, and the dotted blue lines the ±1 variation on the expected limits. ATLAS EPS 2011 limits are from [17] and LEP results from [59]. 7 Summary This note reports a search for new physics in final states containing high-p T jets, missing transverse momentum and no electrons or muons, based on the full dataset (4.7 fb 1 ) recorded by the ATLAS experiment at the LHC in Good agreement is seen between the numbers of events observed in the data and the numbers of events expected from SM processes. The results are interpreted in both a simplified model containing only squarks of the first two generations, a gluino octet and a massless neutralino, as well as in MSUGRA/CMSSM models with tan = 10, A 0 = 0 and µ>0. In the simplified model, gluino masses below 940 GeV and squark masses below 1380 GeV are excluded at the 95% confidence level. In the MSUGRA/CMSSM models, values of m 1/2 < 300 GeV are excluded for all values of m 0, and m 1/2 < 680 GeV for low m 0. Equal mass squarks and gluinos are excluded below 1400 GeV in both scenarios. References (GeV) m LSP [1] L. Evans and P. Bryant, LHC Machine, JINST 3 (2008) S pp ~ q ~ q, ~ q q + LSP; m( ~ g)>>m( ~ q ) P 2 P 1 CMS Preliminary -1 s = 7 TeV L=1.1 fb α T σ σ σ prod prod prod NLO-QCD NLO-QCD σ NLO-QCD = σ = 3 = 1/3 σ q m~ q (GeV) q q χ 0 χ 0 ) s 95% CL upper limit on σ (pb) (CL (GeV) m χ 0 pp ~ g ~ g, ~ g q q χ 0 ; m( ~ q)>>m( ~ g ) CMS Preliminary -1 s = 7 TeV L=1.1 fb α T σ σ σ prod prod prod NLO-QCD NLO-QCD σ NLO-QCD = σ = 3 = 1/3 σ m~ g (GeV) P 2 P 1 g g q q q q χ 0 χ 0 ) s (pb) (CL σ 95% CL upper limit on -1

33 SSSM equal MSSM intermediate MSSM heavy MSSM M 3 = 5 TeV g M 3 =2M q g M 3 = 5 TeV g M q M q L,R;1,2 M 3 = M q g, q L,R;1,2 M q q L,R;1,2 M q q L,R;1,2 M q to < M q LSP M q LSP M q LSP M q LSP

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35 pp colored superpartners pb MSSM, M 3 M q MSSM, M 3 2 M q MSSM, M 3 5 TeV SSSM M q GeV

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37 squark mass [GeV] Squark-gluino-neutralino model, m(χ 0 ) = 0 GeV 1 Cl Cl Cl Cm Cm Cl Cl Cm Cm Cm Et Et Cm Cl Am Cm Dt Dt Dt Et Cm A Am Cl Dt Bt Bt Dt Am Am Am Cm Bt Bt Bt At Am Am A Am ATLAS Combined At At Am Am Am A Preliminary CL s observed 95% C.L. limit CL s median expected limit Expected limit ±1 σ ATLAS EPS L dt = 4.71 fb, At At At Am A A At At At Am A A s=7 TeV gluino mass [GeV] Requirement igure 38: 95% CL s exclusion limits obtained by using The three m e the (incl.) selections signal listed inregion the final row denote with the tight, the medium best and loose expecte selections Channel A A B C D E E miss T [GeV] > 160 p T ( j 1 ) [GeV] > 130 p T ( j 2 ) [GeV] > 60 p T ( j 3 ) [GeV] > p T ( j 4 ) [GeV] > p T ( j 5 ) [GeV] > p T ( j 6 ) [GeV] > 40 (jet, E miss T ) min > 0.4 (i = {1, 2, (3)}) 0.4 (i = {1, 2, 3}), 0.2 (p T > 40 GeV jets) E miss T /m e (Nj) > 0.3 (2j) 0.4 (2j) 0.25 (3j) 0.25 (4j) 0.2 (5j) 0.15 (6j) m e (incl.) [GeV] > 1900/1400/ /1200/ 1900/ / 1500/1200/ / / 1400/1200/900 Table 1: Cuts used to define each of the channels in the analysis. The ET miss /m e cut in any N jet channel uses a value of m e constructed from only the leading N jets (indicated in parentheses). However, the final m e (incl.) selection, which is used to define the signal regions, includes all jets with p T > 40 GeV. respectively. Not all channels include all three SRs.

38 reconstructed primary vertex associated with five or more tracks. This analysis aims to search for the production of heavy SUSY particles decaying into jets and neutralinos, with the latter creating missing transverse momentum (ET miss ). Because of the high mass scale expected for the SUSY signal, the e ective mass, m e, is a powerful discriminant between the signal and most Standard Model backgrounds. For a channel which selects events with N jets, m e is defined to be the scalar sum of the transverse momenta of the leading N jets together with ET miss. The final signal selection uses cuts on m e (incl.) which sums over all jets with p T > 40 GeV. Cuts on m e and E miss, which suppress the multi-jet background, formed the basis of the previous ATLAS jets E miss

39 squark mass [GeV] Squark-gluino-neutralino model, m(χ 0 ) = 0 GeV 1 Cl Cl Cl Cm Cm Cl Cl Cm Cm Cm Et Et Cm Cl Am Cm Dt Dt Dt Et Cm A Am Cl Dt Bt Bt Dt Am Am Am Cm Bt Bt Bt At Am Am A Am ATLAS Combined At At Am Am Am A Preliminary CL s observed 95% C.L. limit CL s median expected limit Expected limit ±1 σ ATLAS EPS L dt = 4.71 fb, At At At Am A A 13 At At At Am A A Process s=7 TeV Data 210 Data local p-value (Gaus. ) 0.55(-0.14) local p-value (Gaus. 0.21(0.8) ) 0.55(-0.14) 0.65(-0.4) 0.21(0.8) 0.9(-1.3) 0.6(-0.26) 0.65(-0. UL on N BSM 58( ) UL on N 84( ) 25( ) 29( ( ) BSM 58( ) 84( ) 25( UL on BSM /(fb) 12( UL ) on BSM 18(1511 /(fb) 20 ) 12(13 5.3( ) 8.2 ) 18( ( )) 3.7( ( ) Signal Region Signal Region Process Process SRC loose SRE SRA loose tight SRA SRB medium tight SRA tight SRC medium tight SRC SRBSRD medium tight tight t t+ Single Top t t+ Single 74 ± 13 Top(75) ± ± (0.046) (64) t t+ Single 0.21 Top 7 ± (5.1) (0.066) 0.22 ± ± 3.4 ± (0.046) 1.6 (10) (0.96) ± 2 ± 0.33 ± (10) (0.066) (0.92) Z/ +jets Z/ 70 +jets ± 22 (61) ± (3.1) (13) Z/ +jets ± (34) (1.6) 2.9 ± ± 20 (3.1) ± 1.1 (69)(4.4) ± ± 0.58 (16) (1.6) (2.7) W+jets W+jets 62 ± 9.3 (61) ± (23) (1.9) W+jets ± (21) (0.84) 2.1 ± ± 4.6 ± (1.9) 1.2 (30) (2.7) ± ± 1.5 (0.84) (11) (2.5) Multi-jets Multi-jets 0.39 ± 0.4 (0.16) 0 ± ± 1.9 (0.002) (3.8) Multi-jets ± ± 0.24 (0.0032) (0.13) 0 ± ± (0.002) (0.38) (0.0023) ± ± (0.0032) (0.013) (0.021) 0 Di-Bosons Di-Bosons 7.9 ± 4 (7.9) ± (4.2) (2) Di-Bosons ± (7.5) (1.9) 1.7 ± ± 7.4 ± 0.26 (2) (16)(0.51) 1.7 ± ± 1.2 (1.7) (1.9) (2.2) Total 214 Total ± 24.9 ± ± ± ± Total ± ± ± ± ± 19 ± ± 9.69 ± ± ± 1.7 ± 4.77 ± Data Data Data local p-value (Gaus. local ) p-value 0.55(-0.14) (Gaus. ) 0.98(-2.1) 0.21(0.8) local p-value (Gaus. 0.65(-0.4) 0.95(-1.7) ) 0.98(-2.1) 0.9(-1.3) 0.018(2.1) 0.95(-1.7) 0.6(-0.26) 0.29(0.55) UL on N UL on N BSM 2.9( BSM 58( ) 84( ) UL on N BSM 25( ( ) ) 2.9(6.1 29( ( ) 60 ) 15 ) 3.1( ( ( ) ) UL on UL on BSM /(fb) 0.62( BSM /(fb) 12( ) 18( UL 1.9 ) ) on BSM /(fb) 0.65( ( ) 1.8 ) 0.62( ( ( ) ) 3.2 ) 0.65( ( ( )) Signal Region Table 3: Observed Process numbers Table of events 3: Observed in data and numbers fitted background of eventscomponents in data andinfitted each SR. background For the total compone backg gluino mass [GeV] give the systematic and statistical give thesra (MC systematic tight and CR combined) and statistical SRB tight uncertainties (MC andsrc respectively. CRtight combined) For the uncertainties SRD tight individual background respect SRE are given, with t t+ Single the values Top in areparenthesis given, 0.22 ± 0.35 with (0.046) indicating the values 0.21 the± pre-fit 0.33 in parenthesis (0.066) predictions 1.8 indicating ± for 1.6 the (0.96) MCthe expectations. pre-fit 2 ± 1.7 predictions (0.92) For W+jets, 3.9 for± Zt 4 igure 38: 95% CL s exclusion limits obtained are from ALPGEN, by and using scaled areby from the additional ALPGEN, signal factors andof scaled 0.75, region 0.78 by additional and 0.73 with respectively, factors the of 0.75, determined best 0.78expecte by andnormalisatio 0.73 resp Z/ +jets 2.9 ± 1.5 (3.1) 2.5 ± 1.4 (1.6) 2.1 ± 1.1 (4.4) 0.95 ± 0.58 (2.7) 3.2 ± ) 2.7 )

40 AmAtAt'BtClCmDtEm AmAtAt'BtClCmDtEm AmAtAt'BtClCmDtEm AmAtAt'BtClCmDtEm

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42 > 25 GeV is found. re required to satisfy H T > 275 GeV. As the main discriminator against QCD m ion the variable T, defined for di-jet events as: T = E T jet 2 M T = 2 i=1 E T jet i 2 E T jet 2 2 i=1 pjet i x 2 2 i=1 pjet i y 2, 10 T calo, and 3 events with R miss = H/ T /E/ calo T > 1.25 are rejected. events/bin/fb and events are required to have T > In events with jet multiplicity n > 2 jets are formed following Ref. [1] and Eq. 2 is applied to the pseudo-jets SUSY ct against multiple jets failing the E Z->νν+jets Z T > 50 GeV selection requirement, the jet- QCD of the missing transverse energy, H/ T, is compared to the calorimeter tower-based to protect against severe energy losses, events with significant jet mismeasurem 10 2 by masked regions in the ECAL (which amount to about 1% of the ECAL ch or by missing instrumentation in the barrel-endcap 10 gap, are removed with the fo edure. The 1 jet-based estimate of the missing transverse energy, H/ T, is used to id t likely to have given rise to the H/ T as those whose momentum is closest in 10 which results 0 after removing them from the event. The azimuthal distance bet

43 ow search for an H T = i=1 n E T jet i ried out in Refs. [8 Events / CMS Preliminary 2011 (b) Comparison of the jet m and MC for the hadronic sel and H/ T > 100 GeV. -1 L dt = 1.1 fb, s = 7 TeV Data Standard Model QCD MultiJet tt, W, Z + Jets LM4 LM α T

44 T value, for 1.1 fb of data collected in H T Bin (GeV) p leading T (GeV) p second T (GeV) p other T (GeV) T > T < R T (10 5 ) 1.36 ± 0.05 stat 1.36 ± 0.08 stat 1.21 ± 0.09 stat 1.21 ± 0.15 stat H Bin (GeV) ± 0.05 stat 1.36 ± 0.08 stat 1.21 ± 0.09 stat 1.21 ± 0.15 stat ± 0.26 stat 0.87 ± 0.36 stat 1.03 ± 0.60 stat 0.39 ± 0.52 stat

45 P 2 P 1 g g q q q χ 0 χ 0 (GeV) m χ 0 pp ~ g ~ g, CMS Preliminary -1 s = 7 TeV L=1.1 fb α T ~ g q q χ 0 ; m( ~ q)>>m( ~ g ) σ σ σ prod prod prod NLO-QCD NLO-QCD σ NLO-QCD = σ = 3 = 1/3 σ ) s (pb) (CL σ 95% CL upper limit on -1 P 2 P 1 q q q q q χ 0 χ 0 (GeV) m LSP pp ~ q ~ q, m~ g (GeV) CMS Preliminary -1 s = 7 TeV L=1.1 fb α T ~ q q + LSP; m( ~ g)>>m( ~ q ) σ σ σ prod prod prod NLO-QCD NLO-QCD σ NLO-QCD = σ = 3 = 1/3 σ m~ q (GeV) ) s 95% CL upper limit on σ (pb) (CL

46 a b c d e f g h a b c d e f g h a b c d e f g h a b c d e f g h

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48 1500 pp colored superpartners pb MSSM, M 3 M q MSSM, M 3 2 M q MSSM, M 3 5 TeV SSSM AmAtAt'BtClCmDtEm AmAtAt'BtClCmDtEm M q GeV

49 pp colored superpartners pb MSSM, M 3 M q MSSM, M 3 2 M q MSSM, M 3 5 TeV SSSM a b c d e f g h a b c d e f g h M q GeV

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51 10 1 ssquarks HpbL QCD only M q é HGeVL FIG. 8: Impact of turning on electroweak gauginos at di erent masses, with M w = M b. The ratio M w /M q is represented by the di erent colors; green: 1, black =.5, blue:.2, red =.1. The solid purple line is the QCD-only cross-section provided for comparison.

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