Supersoft Supersymmetry at the LHC. Mainz, Jan 22 nd, 2013

Transcription

1 Supersoft Supersymmetry at the LHC Mainz, Jan 22 nd,

2 Outline 1. Brief Intro 2. Dirac Gauginos and Supersoft Supersymmetry 3. Colored Superpartner LHC 4. Jets + missing searches for LHC ex.) ATLAS; CMS αt; 5. Further extensions, directions 6. Conclusions 2

3 Where s SUSY? in simplified, yet generic cases, limits on MSSM colored sparticles are pushed to ~1.5 TeV... limits are driven by jet + ME T channels, though many other searches ATLAS jets + MET August

4 4

5 [from J. Lykken] 5

6 Escape routes? make it unnatural: heavy squarks (especially 1st, 2nd generation), though 3rd gen. limits are catching up deplete MET: R-parity violation deplete visible energy: compressed spectra, long/complicated cascades go Dirac/supersoft 6

7 A little reminder SUSY in hidden sector, communicated to MSSM via messengers at scale Mmess SUSY parameterized by soft-masses describe soft masses with higher-dim. operators involving spurions (X = θ 2 F, etc.), & suppressed by messenger scale L d 4 θκ QQ X i X i M 2 mess, d 2 θω Y X M mess W Y W Y, etc. d 2 θλ X M mess H u QU R κ F 2 M 2 mess Q Q m 2 Q Q Q ω Y F M mess λ Y λ Y m 1/2 λ Y λ Y RG run operators from Mmess to EW scale 7

8 A little reminder SUSY in hidden sector, communicated to MSSM via messengers at scale Mmess SUSY parameterized by soft-masses describe soft masses with higher-dim. operators involving spurions (X = θ 2 F, etc.), & suppressed by messenger scale L d 4 θκ QQ X i X i M 2 mess, d 2 θω Y X M mess W Y W Y, etc. d 2 θλ X M mess H u QU R κ F 2 M 2 mess Q Q m 2 Q Q Q ω Y F M mess λ Y λ Y m 1/2 λ Y λ Y RG run operators from Mmess to EW scale 7

9 What about Dirac masses? M3 λψ vs. M3 λλ simple change has big implications requires communicating SUSY breaking to gauginos through D-term spurions: Polchinski, Susskind (1982) Hall, Randall (1991) Fox, Nelson, Weiner (2002)... W α = θ α D Dirac gaugino masses arise from: d 2 θ 2 W α W α a Φ a M mess +h.c. D M mess λ a ψ a + M D λ a ψ a + 8

10 Extra matter we have to give up minimality to get Dirac masses.. added new adjoint superfields Φa for each gauge group d 2 θ 2 W α W α a Φ a M mess M D (A a + A a ) D a eliminating Da... M 2 D 2 (Aa + A a ) 2 M D (A a + A a ) i g a φ i τ a φ i could also add d 2 θ W αw αφ a Φ a M 2 mess +h.c. opposite sign mass terms for Re [Aa], Im[Aa] 9

11 Supersoft SUSY δ m 2 Q { mλ squark/slepton masses generated at loop level mλ m 2 Q =4g 2 i C i (φ) d 4 k (2π) 4 1 k 2 1 k 2 M 2 D + M 2 D k 2 (k 2 m 2 adj ) M 2 D log m 2 adj M 2 D masses are independent of Mmess! 10

12 { Supersoft SUSY δ m 2 Q squark/slepton masses generated at loop level vs. in usual MSSM case m 2 Q =4g 2 i C i (φ) d 4 k (2π) 4 1 k 2 1 k 2 M 2 D + M 2 D M 2 D log k 2 (k 2 m 2 adj ) Λ 2 M 2 D 11

13 { Supersoft SUSY δ m 2 Q squark/slepton masses generated at loop level vs. in usual MSSM case m 2 Q =4g 2 i C i (φ) d 4 k (2π) 4 1 k 2 1 k 2 M 2 D Λ 2 + M 2 k 2 (k 2 D log M M 2 2 D log mess m 2 adj ) M 2 D M 2 D 11

14 Supersoft SUSY mass Dirac gauginos: lighter initial m Q no effect in m Q running dubbed supersoft TeV Mmess 12

15 Supersoft SUSY mass Dirac gauginos: lighter initial m Q no effect in m Q running dubbed supersoft TeV Mmess 12

16 Supersoft SUSY mass Dirac gauginos: lighter initial m Q no effect in m Q running dubbed supersoft TeV Mmess gluinos can easily be several TeV, while the squarks are TeV 12

17 Supersoft SUSY: naturalness δm²h : compare the MSSM and supersoft MSSM supersoft 1-loop: δm 2 H u = 3λ2 t Λ2 M 8π2 2 t log M 2 t δm 2 H u = 3λ2 t 8π 2 M 2 t log M 2 3 M 2 t 2-loop: δm 2 H u = λ2 t 2π 2 α s π M 3 2 log Λ2 M (finite) plug in numbers: log m2 adj M3 2 =1.5 Λ = 20 M 3 M 2 t = 3α s 4π M 2 3 tuning for: (M 3 ) Maj =900GeV 13

18 Supersoft SUSY: naturalness δm²h : compare the MSSM and supersoft MSSM supersoft 1-loop: δm 2 H u = 3λ2 t Λ2 M 8π2 2 t log M 2 t δm 2 H u = 3λ2 t 8π 2 M 2 t log M 2 3 M 2 t 2-loop: δm 2 H u = λ2 t 2π 2 α s π M 3 2 log Λ2 M (finite) plug in numbers: log m2 adj M3 2 =1.5 Λ = 20 M 3 M 2 t = 3α s 4π M 2 3 tuning for: (M 3 ) Maj =900GeV (M 3 ) Dir =5.0TeV 13

19 Supersoft SUSY: naturalness δm²h : compare the MSSM and supersoft MSSM supersoft 1-loop: δm 2 H u = 3λ2 t Λ2 M 8π2 2 t log M 2 t δm 2 H u = 3λ2 t 8π 2 M 2 t log M 2 3 M 2 t 2-loop: δm 2 H u = λ2 t 2π 2 α s π M 3 2 log Λ2 M (finite) plug in numbers: log m2 adj M3 2 =1.5 Λ = 20 M 3 M 2 t = 3α s 4π M 2 3 tuning for: (M 3 ) Maj =900GeV (M 3 ) Dir =5.0TeV substantially heavier gluino just as natural in supersoft 13

20 Why not supersoft? sounds great so far, as we can have heavier sparticles and stay natural BUT, recall: d 2 θ 2 W α Wa α Φ a M mess M D (A a + A a ) D a +... EOM for Re[Aa]: L Re(A a ) = D a =0 SU(2)w, U(1)Y D-terms = Higgs quartic -> tree level Higgs mass so if EW gauginos are Dirac then mh = 0 at tree level! m 2 h = m 2 Z cos 2 2β + 3 4π 2 cos2 α y 2 t m 2 t ln m t 1 m t 2 m 2 t 14

21 Why not supersoft? pure supersoft won t work. We could... keep winos, binos Majorana make stops very heavy (>10 TeV) NMSSM-ology add other sources of SUSY... production of squarks/gluinos basically independent of how we repair EW/Higgs sector so: focus on collider ramifications for now, return to mh issue later 15

22 LHC limits on supersoft 16

23 Supersoft at the LHC heavy Dirac gluino means several colored sparticle production channels are suppressed by kinematics alone q q - g q q - g 17

24 Supersoft at the LHC heavy Dirac gluino means several colored sparticle production channels are suppressed by kinematics alone q q - g q q - g 17

25 Supersoft at LHC suppression goes beyond kinematics: SUSY kinetic terms contain a U(1)R symmetry R[λ] = 1, R[q] = R[q ]-1 preserved by Dirac masses, R[ψ] = -1 restricts processes Q x Q Q Q Q violate R-symmetry Q preserve R-symmetry 18

26 Supersoft at LHC suppression goes beyond kinematics: SUSY kinetic terms contain a U(1)R symmetry R[λ] = 1, R[q] = R[q ]-1 preserved by Dirac masses, R[ψ] = -1 restricts processes Q x Q Q Q Q violate R-symmetry Q preserve R-symmetry 18

27 Supersoft at LHC suppression goes beyond kinematics: SUSY kinetic terms contain a U(1)R symmetry R[λ] = 1, R[q] = R[q ]-1 preserved by Dirac masses, R[ψ] = -1 restricts processes Q x Q Q Q Q violate R-symmetry Q preserve R-symmetry 18

28 Supersoft production 1000 Σpp colored superpartners pb MSSM, M Q M 3 MSSM, M Q 0.5 M 3 MSSM, M 3 5 TeV MRSSM M Q GeV increasing M 3 fewer processes allowed production of colored superstuff with Dirac gluino traditional MSSM 19

29 Supersoft limits form a simplified supersoft model [Kribs, AM 12] heavy gluino, degenerate 1 st, 2 nd gen. squarks (L,R), massless LSP m q 5 TeV 500 GeV to < m q SSSM g q L,R;1,2 LSP and repeat (1-5fb -1 ) jets + MET analyses from ATLAS/CMS [ , , CMS-PAS-SUS , ] signal generated with PYTHIA->Delphes, gets acceptance PROSPINO for K-factor 20

30 Supersoft versus MSSM Simplified Models then perform apples-for-apples comparison against MSSM. 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 from quoted backgrounds + uncertainly, use calculated cross section (NLO), derived acceptance to bound SUSY parameters = MQ 21

31 ATLAS jets + missing search strategy 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 gluino mass [GeV] 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 Requirement T igure 38: 95% CL s exclusion limits obtained by using the signal region with the best expected sensivity at each point in a simplified MSSM scenario with only strong production of gluinos and first- and econd-generation squarks, and direct decays to jets and neutralinos (left); and in the (m 0 ; m 1/2 ) plane f MSUGRA/CMSSM for tan β = 10, A 0 = 0 and µ>0 respectively. (right). Not all channels The red include lines all threeshow SRs. the observed limits, 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 φ(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 eff (Nj) > 0.3 (2j) 0.4 (2j) 0.25 (3j) 0.25 (4j) 0.2 (5j) 0.15 (6j) m eff (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 E miss /m eff cut in any N jet channel uses a value of m eff constructed from only the leading N jets (indicated in parentheses). However, the final m eff (incl.) selection, which is used to define the signal regions, includes all jets with p T > 40 GeV. The three m eff (incl.) selections listed in the final row denote the tight, medium and loose selections 22

32 ATLAS Search Bounds AmAtAt'BtClCmDtEm AmAtAt'BtClCmDtEm AmAtAt'BtClCmDtEm AmAtAt'BtClCmDtEm 23

33 CMS αt Search Strategy Triggered >= 2 jets with 0 leptons and 0 photons - ET: all jets > 50 GeV; leading 2 jets > 100 GeV - Cut ow and search count for HT anbins H T = i=1 n E T jet i ried out in Refs. [8 - missing ET > 100 GeV - mild Δφ cut to reduce jet mismeasurement Events / CMS Preliminary 2011 (b) Comparison of the jet mul and MC for the hadronic select and H/ T > 100 GeV. " -1 L dt = 1.1 fb, s = 7 TeV Data Standard Model QCD MultiJet tt, W, Z + Jets LM4 LM6 cut on: αt = ET,jet#2/MT(j1j2) ! T (c) Comparison of the α distribution between data 24

34 CMS Bounds on Simplified Models 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 " T ~ q # q + LSP; m( ~ g)>>m( ~ q )!!! prod prod prod NLO-QCD NLO-QCD! NLO-QCD =! = 3 $ = 1/3 $! m~ q (GeV) ) s 95% CL upper limit on! (pb) (CL 25

35 CMS αt Search Bounds 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 Kribs & AM 26

36 Effectiveness of LHC strategy difference in limits not just difference in cross-section 1500 Σ 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 27

37 Effectiveness of LHC strategy strongest limits on MSSM points come from highest Meff/HT cuts [showed αt, ATLAS jets + MET, also true for CMS MHT, razor searches...] at lower squark mass, where SSSM has comparable cross section, high cuts are very inefficient same σsusy SSSM MSSM searches with a broader HT reach would be useful 28

38 Supersoft limits projection to higher luminosity [Kribs, AM 12] 650 expected limit from most stringent single channel MRSSM squark mass limit GeV jets + MET (CMS) jets +MET (ATLAS) CMS αt CMS razor integrated luminosity fb 1 7 TeV also: limits degrade as MX gets closer to MQ 29

39 Keynote physics 30

40 Implications on other LHC searches R-symmetry prevents same-sign lepton channel for natural μ, large M2, M1 (Dirac): lighest charginos/neutralinos are Higginos, are very degenerate μ χ 0 ₂ χ ± ₁ χ 0 ₁ χ ± 1 χ W ± χ 0 2 χ Z 0 χ 0ᵢ G + h 0 will effect tri-lepton limits... 31

41 Implications on other LHC searches 3rd generation searches: most dedicated stop searches rely on leptons, assume 100% BR to one mode t b χ ± W χ 0 t t χ 0 b W μ M1, M2 = degenerate chargino/neutralino + mixture of stop BR much looser bounds strongest bound from sbottom searches (b-jets + MET) [Kribs, AM, Menon in progress] 32

42 Implications on other LHC searches 3rd generation searches: most dedicated stop searches rely on leptons, assume 100% BR to one mode t b χ ± W χ 0 t t χ 0 b W μ M1, M2 = degenerate chargino/neutralino + mixture of stop BR much looser bounds strongest bound from sbottom searches (b-jets + MET) [Kribs, AM, Menon in progress] 32

43 Implications on other LHC searches 3rd generation searches: most dedicated stop searches rely on leptons, assume 100% BR to one mode t b χ ± W χ 0 t t χ 0 b W μ M1, M2 = degenerate chargino/neutralino + mixture of stop BR much looser bounds strongest bound from sbottom searches (b-jets + MET) region with light stops still allowed, a supernatural setup t L,b L,b R t R 400 GeV µ 100 GeV [Kribs, AM, Menon in progress] 32

44 Implications on other LHC searches is there a smoking - gun signal for the dirac setup? YES: extra states, the scalars in Φᵢ = Aᵢ Re[Aᵢ] are heavy, mass ~ MD, Im[Aᵢ] can be light Aᵢ are R-parity even they can be singly produced, though only tree-level interactions involve gauge fields.. 33

45 Implications on other LHC searches is there a smoking - gun signal for the dirac setup? YES: extra states, the scalars in Φᵢ = Aᵢ Re[Aᵢ] are heavy, mass ~ MD, Im[Aᵢ] can be light Aᵢ are R-parity even they can be singly produced, though only tree-level interactions involve gauge fields.. single production looks hopeless Aᵢ 33

46 Implications on other LHC searches is there a smoking - gun signal for the dirac setup? YES: extra states, the scalars in Φᵢ = Aᵢ Re[Aᵢ] are heavy, mass ~ MD, Im[Aᵢ] can be light Aᵢ are R-parity even they can be singly produced, though only tree-level interactions involve gauge fields.. single production looks hopeless pair production better: Aᵢ Aᵢ Aᵢ 33

47 Implications on other LHC searches is there a smoking - gun signal for the dirac setup? YES: extra states, the scalars in Φᵢ = Aᵢ Re[Aᵢ] are heavy, mass ~ MD, Im[Aᵢ] can be light Aᵢ are R-parity even they can be singly produced, though only tree-level interactions involve gauge fields.. single production looks hopeless pair production better: Aᵢ Aᵢ Aᵢ pp equal mass di-jet resonances 33

48 Implications on other LHC searches is there a smoking - gun signal for the dirac setup? YES: extra states, the scalars in Φᵢ = Aᵢ Re[Aᵢ] are heavy, mass ~ MD, Im[Aᵢ] can be light Aᵢ are R-parity even they can be singly produced, though only tree-level interactions involve gauge fields.. single production looks hopeless pair production better: Aᵢ Aᵢ pp equal mass di-jet resonances see Plehn, Tait 08, also CMS-EXO , ATLAS Aᵢ 33

49 Implications on other LHC searches is there a smoking - gun signal for the dirac setup? YES: extra states, the scalars in Φᵢ = Aᵢ Re[Aᵢ] are heavy, mass ~ MD, Im[Aᵢ] can be light Aᵢ are R-parity even they can be singly produced, though only tree-level interactions involve gauge fields.. single production looks hopeless pair production better: Aᵢ Aᵢ pp equal mass di-jet resonances see Plehn, Tait 08, also CMS-EXO , ATLAS EW Aᵢ production unexplored Aᵢ 33

50 .. About that Higgs mass some example fixes for λh,tree= 0 1.) extend the EW-sector (nmssmology): ex.) add in Ru = (1,2)-1/2, Rd = (1,2)+1/2 R[Ru] = R[Rd] = 2 allows: W κ Hu ΦB Ru + u d implies (schematically) V (h) = m2 0 2 h M D a g 2 h2 2 + κ µh 2 a + 34

51 .. About that Higgs mass some example fixes for λh,tree= 0 1.) extend the EW-sector (nmssmology): maintains R-symmetry ex.) add in Ru = (1,2)-1/2, Rd = (1,2)+1/2 R[Ru] = R[Rd] = 2 allows: W κ Hu ΦB Ru + u d implies (schematically) V (h) = m2 0 2 h M D a g 2 h2 2 + κ µh 2 a + 34

52 .. About that Higgs mass some example fixes for λh,tree= 0 1.) extend the EW-sector (nmssmology): maintains R-symmetry ex.) add in Ru = (1,2)-1/2, Rd = (1,2)+1/2 R[Ru] = R[Rd] = 2 allows: W κ Hu ΦB Ru + u d implies (schematically) V (h) = m2 0 2 h M D a g 2 h2 2 + κ µh 2 a + a gh2 4 M D 34

53 .. About that Higgs mass some example fixes for λh,tree= 0 1.) extend the EW-sector (nmssmology): maintains R-symmetry ex.) add in Ru = (1,2)-1/2, Rd = (1,2)+1/2 R[Ru] = R[Rd] = 2 allows: W κ Hu ΦB Ru + u d implies (schematically) V (h) = m2 0 2 h M D a g 2 h2 2 + κ µh 2 a + a gh2 4 M D becomes effective quartic 34

54 .. About that Higgs mass 1.) mass term for Φᵢ: δv (h) =m 2 a a 2 requires a second SUSY-breaking spurion: X = θ²f provided X is not a singlet, can t write X WαW α, gauginos still Dirac [Kribs, Okui, Roy 11] but matter can get mass via: X X ΦB ΦB M 2 mess generates quartic g2 m 2 a 32 M 2 D 35

55 .. About that Higgs mass 1.) mass term for Φᵢ: δv (h) =m 2 a a 2 requires a second SUSY-breaking spurion: X = θ²f provided X is not a singlet, can t write X WαW α, gauginos still Dirac [Kribs, Okui, Roy 11] but matter can get mass via: X X ΦB ΦB M 2 mess generates quartic g2 m 2 a 32 M 2 D 1+2.) charge X under U(1)R preserved by SUSY kinetic terms, R [X] = 2. add matter to enforce R-symm throughout = MRSSM [Kribs, Poppitz, Weiner 07] 35

56 mrssm W µ u H u R u + µ d R d H d W λ u B Φ B H u R u + λ d B Φ B R d H d + λ u W Φ a W H u τ a R u + λ d W Φ a W R d τ a H d can get mh~125 GeV and strong EWPT Λ W 0 M 2 =1TeV µ u = µ d = 200 GeV m( t L,R )=3TeV m a = Λ B [Fok, Kribs, AM, Tsai 12] 36

57 mrssm W µ u H u R u + µ d R d H d W λ u B Φ B H u R u + λ d B Φ B R d H d + λ u W Φ a W H u τ a R u + λ d W Φ a W R d τ a H d can get mh~125 GeV and strong EWPT Λ W 0 M 2 =1TeV µ u = µ d = 200 GeV m( t L,R )=3TeV m a = Λ B [Fok, Kribs, AM, Tsai 12] 36

58 Conclusions Dirac gauginos (supersoft SUSY): naturally very heavy, U(1)R preserved significantly reduced colored sparticle production limits ( 5 fb-1, 8 TeV data): ~ GeV - analysis optimized for high HT do poorly limits ~ independent of EW sector, which cannot be pure supersoft & achieve mh ~125 GeV X - many interesting directions to go in from here! 37