SUSY at LHC now and future Mihoko Nojiri KEK& IPMU FermiLab - PowerPoint PPT Presentation

SUSY at LHC now and future Mihoko Nojiri KEK& IPMU FermiLab 9/29

SUSY after LHC Checking current excess (ATLAS 1l+ missing +jets Han, Nojiri, Takeuchi, Yanagida (arXiv tomorrow…) Future: various direction… ex : application of quark gluon separation to get max sensitivity Bhattacherjee, Mukhopadhyay, Nojiri, Sakaki , Webber arXiv Today 1609.08781

SUSY at LHC Now

current excess (stop channel) ATLAS 1l + missing + jets Signal region SR1 tN high bC2x diag bC2x med bCbv DM low DM high ( n j , n b ) ( ≥ 4 , ≥ 1) ( ≥ 4 , ≥ 1) ( ≥ 4 , ≥ 2) ( ≥ 4 , ≥ 2) ( ≥ 2 , = 0) ( ≥ 4 , ≥ 1) ( ≥ 4 , ≥ 1) E / T [GeV] 260 450 230 210 360 300 330 m T [GeV] 170 210 170 140 200 120 220 am T 2 [GeV] 175 175 170 210 - 140 170 Total background 24 ± 3 3 . 8 ± 0 . 8 22 ± 3 13 ± 2 7 . 8 ± 1 . 8 17 ± 2 15 ± 2 Observed 37 5 37 14 7 35 21 p 0 ( � ) 0.012(2.2) 0.26(0.6) 0.004(2.6) 0.40(0.3) 0.50(0) 0.0004(3.3) 0.09(1.3) N limit obs . (95% CL) 26.0 7.2 27.5 9.9 7.2 28.3 15.6 TABLE I: Summary of some of the selection cuts and the results of the seven signal regions defined in ATLAS stop miss ` + jets + / E channel. T excess in various channel though all correlated (stop? )

Some distribution events / 30 GeV ~ ~ ~ -1 ∼ 0 ATLAS Preliminary s = 13 TeV, 13.2 fb t t production, t → t+ χ 700 1 1 1 1 16 [GeV] ATLAS Preliminary Data Total SM Observed limit ( 1 ) ± σ -1 th ~ s = 13 TeV, 13.2 fb ∼ 0 14 t t Z+jets m( t , )=(600,200) 600 χ Expected limit ( ± 1 σ ) Limit at 95% CL 1 exp ~ ∼ 0 W+jets Wt m( t , )=(800,1) 0 1 χ ATLAS stop1L ∼ χ 12 m 1 -1 500 8 TeV + 13 TeV (3.2 fb ) Diboson t t +V SR1 10 400 8 < 0 300 - m t 6 - m 0 ∼ χ 1 200 ~ m t 4 1 100 2 0 0 200 250 300 350 400 450 500 550 600 200 300 400 500 600 700 800 900 1000 m [GeV] miss ~ E [GeV] t 1 T Assume top partner decay into LPS and top Not happy because it is analyzed by simplified model (Kinematics are taken care of, but assume 100% branching ratio to draw contours ) production,

Why simplified model do not capturing the case Han,Nojiri, Takeuchi, Yanagida(arXiv tomorrow or next week) stop_R → Bino LSP case is almost exclude by CMS boosted top search :-( marginal possibility in degenerate region CMS -1 12.9 fb (13 TeV) Preliminary Bino LSP 2 700 10 [GeV] ~ ~ ~ ∼ 95% CL upper limit on cross section [pb] χ pp → t t , t → t 0 NLO+NLL exclusion 700 1 Observed ± 1 σ CMS _ boosted 600 theory 0 1 ∼ χ Expected 1 ± σ 10 m experiment 500 600 CMS _ hadronic 1 0 0 m m ∼ ∼ χ χ 1 1 400 + + m m ATLAS _ 1L t t = = m m ~ ~ t t 500 300 -1 10 200 M χ 0 [ GeV ] 400 2 σ lower -2 10 100 -3 300 0 10 200 400 600 800 1000 1200 m [GeV] ~ t 200 central 2 σ u p p e r 1 σ upper 1 σ lower 100 0 500 600 700 800 900 1000 M stop [ GeV ]

How about light Higgsino? even worse? :-( CMS PAS SUS-16-029 Higgsino LSP 700 CMS _ boosted 600 CMS _ hadronic channels less 50% t 50 %b ATLAS _ 1L than expected 500 M χ 0 [ GeV ] 400 SR42 2 σ lower 300 200 1 σ lower central SR 40, 41 100 LEP 1 σ upper 0 500 600 700 800 900 1000 M stop [ GeV ] SR 40,41 2 b jet ETmiss and b is not consistent with t Nj=5~7, not boosted top and W, ETmiss> 450 Note: channels more than expected and channels less than expected tend to overlap

more complicated decay pattern Need to 1. Reduce branch into stop to t chi 2. Keep lepton branch stop(right handed) → higgsino → bino W . * * *dark matter search constraint from Higgsino Bino mixing *Dark matter density can be adjusted by bin-slepton co-annihiliation Higgsino - Bino distribution is not sexy but OK 700 CMS _ boosted 650 - 350 600 CMS _ hadronic 15 750 - 300 800 - 200 ATLAS _ 1L events / 30 GeV LUX 500 BP ⨯ 10 M χ 0 [ GeV ] 400 r e w l o 2 σ ⨯ 5 300 ⨯ 0 200 ⨯ central 200 300 400 500 600 1 σ lower miss ( GeV ) E T 100 2 σ u p 1 σ upper p e r - bottom line: 0 We need to wait 500 600 700 800 900 1000 M stop [ GeV ]

SUSY at LHC Future

BSM search in Future Monojet High Luminosity is possible but No 6 100 TeV, 30 ab - 1 large energy increase for a moment. 5 100 TeV, 3 ab - 1 14 TeV, 3 ab - 1 4 Significance Significance is expressed at 1 % syst 3 5 % syst S/ √ ( B + ( δ B)^2 ) where δ B is 2 systematical error of the 1 background 0 500 1000 1500 2000 M c @ GeV D clean channel extend with Figure 2. Reach of monojet searches. luminosity. → Theoretical error Cirelli et al ‘14 will reduce drastically at NNLO New method which can reduce I am going to talk about background might also be application of quark/gluon useful. separation

What we may expect ex ： gluino → qq X quark and gluon initiated jet are different: In parton shower, quark split into hard quark and soft gluon and gluon split into two gluon more equally. ME level pp-> gluino gluino-> 4q +missing: background Z+jets more gluons. − f j 1 f j 2 f j 3 f j 4 Process q q q q contamination of ISR especially g ˜ ˜ g + jets 0.92 0.87 0.77 0.64 compressed spectrum Z + jets 0.64 0.55 0.27 0.16 background also contains quark especially for the first jet. (Mgluino, Mchi) =(1750 GeV,750GeV ) Meff> 1.8TeV (we have checked Matrix level ISR generation is not necessary for this level of compressed spectrum (Fraction is calculated following parton shower history)

experimental data recent experimental study in data driven approach. • γ j or Z j: jet is more likely to be quark • 2j event: Low pt: dominated by gluon jet, High pt quark and gluon jet CMS Simulation Preliminary, s = 8 TeV CMS Simulation Preliminary, s = 8 TeV 1 0.2 Normalized To Unity Quark Jet Efficiency 40 < p < 50 GeV 0.18 | | < 2 η T Quark Jets 0.8 0.16 Gluon Jets 0.14 0.6 0.12 0.1 0.08 0.4 Quark-Gluon LD 0.06 | | < 2, 40 < p < 50 GeV η T 0.04 0.2 | | < 2, 80 < p < 100 GeV η T 3 < | | < 4.7, 40 < p < 50 GeV η 0.02 T 0 0 0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 Gluon Jet Rejection Quark-Gluon Likelihood Discriminant Discriminant ( BDT score)

Preliminary Preliminary Preliminary Preliminary What is discriminant re-sum needed soft physics w trk 1/Events 0.14 ATLAS Preliminary 0.12 -1 s = 8 TeV 20.3 fb 0.1 90 GeV < P < 120 GeV, | η | < 0.8 T i , j ∈ jet E T , i E T , j ( ∆ R i , j ) β 0.08 Extracted Herwig++ Pythia 8 P X 0.06 C β = n trk = 0.04 Light Quarks 0.02 ⌘ 2 ⇣P 0 i ∈ jet E T , i 1/Events 0.14 trk ∈ jet 0.12 0.1 0.08 0.06 0.04 Gluons P const ∈ jet p T , const ∆ R const , jet 0.02 0 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 w calo = P const ∈ jet p T , const w ……….. trk P trk ∈ jet p T , trk ∆ R trk , jet w trk = P trk ∈ jet p T , trk experimentally different ROC CMS Simulation Preliminary, s = 8 TeV CMS Simulation Preliminary, s = 8 TeV 1 0.2 Normalized To Unity Quark Jet Efficiency build a function which give 40 < p < 50 GeV 0.18 | | < 2 η T Quark Jets gluon jet ~0 an quark~1 0.16 0.8 Gluon Jets 0.14 0.6 0.12 0.1 This function depend 0.08 0.4 Quark-Gluon LD 0.06 on method you use to | η | < 2, 40 < p < 50 GeV T 0.04 0.2 | | < 2, 80 < p < 100 GeV η T build the function 3 < | | < 4.7, 40 < p < 50 GeV η 0.02 T 0 0 0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 Gluon Jet Rejection Quark-Gluon Likelihood Discriminant

Fraction of quark gluon jet in MC 1 1 Fraction of Events Fraction of Events ATLAS Preliminary ATLAS Preliminary 0.9 Dijet 0.9 Dijet Simulation, s = 8 TeV Simulation, s = 8 TeV Pythia 8 Pythia 8 0.8 0.8 | | < 0.8 1.2 < | | < 2.1 η η Herwig++ Herwig++ 0.7 0.7 0.6 0.6 0.5 0.5 0.4 0.4 0.3 0.3 Gluons Light Quarks Gluons Light Quarks 0.2 0.2 Charms Bottoms Charms Bottoms 0.1 0.1 0 0 50 100 150 200 250 300 350 400 50 100 150 200 250 300 350 400 Jet P (GeV) Jet P (GeV) T T 1 1 Fraction of Events Fraction of Events 0.9 0.9 0.8 0.8 0.7 0.7 0.6 0.6 +jet +jet γ γ ATLAS Preliminary ATLAS Preliminary Pythia 8 Pythia 8 0.5 0.5 Simulation, s = 8 TeV Simulation, s = 8 TeV Herwig++ Herwig++ 0.4 0.4 | | < 0.8 1.2 < | | < 2.1 η η Gluons Charms Gluons Charms 0.3 0.3 Bottoms Bottoms 0.2 0.2 0.1 0.1 0 0 50 100 150 200 250 300 350 400 50 100 150 200 250 300 350 400 Jet P (GeV) Jet P (GeV) T T