CMS Status and SUSY Searches with 3 rd Generations

Transcription

1 CMS Status and SUSY Searches with 3 rd Generations Teruki Kamon 1,2) for CMS Collaboration and TAMU-KNU PPC Collaboration 1) TAMU, 2) Kyungpook National Univ., Korea Joint Korea-France Collider Physics Workshop (KRFR2010) KNU, Daegu, Korea June 28, 2010 CMS & SUSY 1

2 OUTLINE Status of the CMS Experiment Detector Commissioning to Physics Objects Thinking of SUSY Searches Smoking-gun Signals with 3 rd Generation Particles Data-driven Dijet Mass : W jj Summary Teruki Kamon 2

3 Status of CMS Experiment Teruki Kamon 3

4 First 2 Months of 7-TeV Operations Reliable operations with ~19nb -1 delivered by LHC and ~17nb -1 of data collected by CMS. Overall data taking efficiency >91%. After quality flags and data certification for physics (~95%) we end up with ~16nb -1 of good data for physics. L cm -2 s -1 L cm -2 s -1 L cm -2 s -1 4

5 Dijet Mass Distributions Jets reconstructed with the anti-k T R=0.5 algorithm Dijet selection : Jet P T > 25 GeV, ΔΦ jj > 2.1, η j < 3 Loose ID cuts on number of components and neutral / charged energy fraction Three different approaches: pure calorimetric, track corrected calo and particle flow. 5

6 High-mass Dijet Event CMS Experiment, Sat Apr , 12:25:05 CEST Run Event Luminosity Section: 285 Dijet Mass : 764 GeV Jet1 p T : 253 GeV Jet2 p T : 244 GeV 6

7 Missing E T in MB Calo jets JPT jets PF jets MC reproduces data over 5 orders of magnitudes MET tails understanding is in progress (still work to do) Performance with γ+jets, W s, Z ICHEP Missing E T Resolution Particle Flow 7

8 B-tagging: 3D IP Significance 3D impact parameter value and its significance (+zoom into 2 region) for all tracks with p T > 1GeV belonging to jets with p T > 40 GeV and η < 1.5 (PFlow Jets anti-k T R=0.5). Two b-jets candidate Excellent alignment and general tracking performance 8

9 Low-mass Resonances Tracks displaced from primary vertex (d 3D > 3σ) Common displaced vertex (L 3D > 10σ) Invariant mass distribution for different combinations (Ω ΛK or Ξ Λπ ) fit to a common vertex. PDG Mass: PDG Mass: Ω ΛK Ξ Λπ 9

10 Low Mass Di-photons 1.46M of π 0 γγ P T (γ) > 0.4 GeV, P T (pair) > 1 GeV 0.43 nb M π k η γγ P T (γ) > 0.5 GeV, P T (pair) > 2.5 GeV Numbers refer to ~10% of the currently available statistics. Very useful tool to intercalibrate the crystals nb k η Note: MC based correction applied according to cluster η and energy 10

11 J/ψ μ + μ All muon tracks, Nhits 11 ( 2 in Pixels) L int = 15 nb -1 Signal events: 1230 ± 47 Sigma: (42.7 ± 1.9) MeV M 0 : ± GeV (stat) S/B = 5.4 (M 0 ± 2.5σ) χ 2 /ndof = 1.1 On going studies Mass w.r.t. η and P T track momentum scale Probe and Tag rates tracking efficiency Flight distance prompt and decay J/ψ from ϒ and B J/ψ + K 11

12 J/ψ e + e Loose low mass cuts in electron selection criteria. Challenging analysis: very promising preliminary results. 12

13 W ± µ ± ν Event selection: Muon ID cuts with Isolation, p T cut and MET Monte Carlo: Cross section normalized to 16 nb -1 integrated luminosity W μν candidate 57 candidates with M T > 50 GeV 13

14 W ± e ± ν Event selection: (a) basic electron ID and no MET cut; (b) more complex electron ID, cuts on E T, MET and ΣE T (see figure) Monte Carlo: cross section normalized to 12 nb -1 integrated luminosity. 40 candidates with M T > 50 GeV 14

15 Z μ + μ Event selection: muon ID selection (global and tracker muons); loose Isolation, pt cut. Monte Carlo: cross section normalized to 16 nb -1 integrated luminosity. 5 Z μ + μ - candidates 15

16 Z e + e Event selection: both electrons with a SuperCluster with E T > 20 GeV Monte Carlo: cross section normalized to 17 nb -1 integrated luminosity 5 Z e + e - candidates 16

17 First 7 TeV PRL (June 18) Transverse Momentum and Pseudorapidity Distributions of Charged Hadrons in pp Collisions at s = 7TeV Rise of the particle density at (2.36) 7 TeV steeper than in model predictions. Careful tuning effort of the MC generators is ongoing. 17

18 Thinking of SUSY Searches CMS commissioning of various physics objects is very smooth. Thinking of SUSY with cosmological connection Analysis Strategy: 3 rd generation objects Top W + b W jj : Data-driven Dijet Mass 18

19 dn dt Phenomenology Projects at a Glance = 3Hn v [Case 1] Coannihilation (CA) Region Arnowitt, Dutta, Gurrola, *) Kamon, Krislock, *) Toback, PRL100 (2008) For earlier studies, see Arnowitt et al., PLB 649 (2007) 73; Arnowitt et al., PLB 639 (2006) 46 [Case 3] HB/Focus Point Region Arnowitt, Dutta, Flanagan, #) Gurrola, *) Kamon, Kolev, Krislock *) (in preparation) [Case 4] Non-universality Arnowitt, Dutta, Kamon, Kolev, Krislock, *) Oh *) Graduate student, #) REU student ( 2 2 σ n ) ( 2 2 = 3Hn σ v n n ) S( φ) n eq [Case 5] LFV Allahverdi, Bornhauser, Dutta, Kamon, Krislock *) [Case 6] Bino-Higgsino Mixing Dutta, Kamon, Krislock, *) Oh dn dt eq + (extra time-dependence) e.g., Quintessence Scalar field dark energy [Case 2] Over-dense Dark Matter Region Dutta, Gurrola, *) Kamon, Krislock, *) Lahanas, Mavromatos, Nanopoulos PRD 79 (2009) Teruki Kamon PPC at the LHC 19

20 Review: 3 msugra Cases tanβ = 40 A 0 = 0, µ > 0 3 HB/Focus Point Region m 0 (GeV) c 2 Note: g 2 data may still be controversial. Over-dense DM Region a b m 1/2 (GeV) Excluded by 1) a Rare B decay b sγ 2) b No CDM candidate 3) c Muon magnetic moment 1 Coannihilation (CA) Region 20

21 m 0 (GeV) a Report Card : Ωh 2 tanβ = 40 A 0 = 0, µ > 0 c b 0 g~ tt ~ χ 2 0 ( Wb)( Wb)( ll ~ χ1 ) 0 ( jjb)( jjb)( ll ~ χ ) B. Dutta Talk at SUSY 2009 June 2009 ~ 0 χ 2 h ~ χ bb ~ χ ~ 0 χ τ m 1/2 (GeV) 2 ± 0 τ τ ~ χ1 Excluded by 1) a Rare B decay b sγ 2) b No CDM candidate 3) c Muon magnetic moment ± PRD 79 (2009) ~ τ PRL100 (2008) δωh 2 Ωh 500 fb -1 2 δωh 2 Ωh 2 δωh 2 Ωh ~ 28% 300 fb fb fb -1 ~ 19% ~ 5% 21

22 New Story Case 4 What? Cosmologically-consistent non-universal SUGRA Who? Abram Krislock, Bhaskar Dutta, Teruki Kamon, Nikolay Kolev, Youngdo Oh Smoking-gun signal W jj in Jets+MET final state How? Mixed Event Dijet Mass (MEDM) 22

23 Non-Universal SUGRA Dutta, Kamon, Kolev, Krislock, Oh msugra - Good enough to confirm that the dark matter is the SUSY weakly-interacting neutral particle. Is a cosmological measurement possible for non-minimal case? 1) Start with over-abundance (x10) region in Case2-like msugra (e.g., m 1/2 = 500, m 0 = 360, m Hu = 360) 2) Reduce µ (Higgs coupling parameter) by increasing m Hu (e.g., m 1/2 = 500, m 0 = 360, m Hu =732) Extra contributions to Ωh 2 More annihilation Less abundance Normal values of Ωh 2 3) Find smoking gun signals 4) Technique to calculate Ωh 2 23

24 Smoking Gun Signal(s) E miss T > 180 GeV; N(J) > 2 with E T > 200 GeV; E miss T + E J1 T + E J2 T > 600 GeV N(j i ) > 2 with p T > 20 GeV ~ χ 1 ~ 0 χ 2 ~ 0 W χ1 ντ~ 1 ττ~ ± 1 Non-U- U 42% SSC 2. 4% ± msugra 58% 98% 92% 99% Finding W s M(j i j k ) A clear peak at the W mass, but can we see the BG shape? 24

25 Data-driven M(jj) Extraction Event Jets M(jj) M(jj) 1 1a, 1b, 1c 2 2a. 2b M(2a, 1a), M(2a, 1b), M(2a, 1c) M(2b, 1a), M(2b, 1b), M(2b, 1c) 3 3a, 3b, 3c, 3d M(3a, 2a), M(3a, 2b), M(3b, 2a), M(3b, 2b), M(3c, 2a), M(3c, 2b), M(3d, 2a), M(3d, 2b) M(2a, 2b) 4 For each j i in Event X, M(j i j k ) is calculated with j k in Event X 1 M(3a, 3b), M(3a, 3c), M(3a, 3d), M(3b, 3c), M(3b, 3d), M(3c, 3d) Mixed Event Dijet Mass (MEDiM) M(jj) > nnn GeV for normalization nnn M(jj) nnn M(jj) 25

26 Dijet mass distribution for any two-jet pairs in the event. W s Dijet mass distribution for any two-jet pairs in the mixed events. BG-subtracted Dijet mass distribution has still residual BG. But, much easier to extract the W s. for any two-jet pairs in the mixed events. Clearly we can see the W events and Sideband BG. 26

27 Start with JW E miss T > 180 GeV; N(J) > 2 with E T > 200 GeV; E miss T + E J1 T + E J2 T > 600 GeV & N(j) > 2 with p T > 30 GeV N(b) > 0 with p T > 30 GeV N(τ) = 0 with p T > 20 GeV & Event Mix to extract W s Note there might be b-jets and/or τ-jets in event, but not counted as J nor j. Ture = 714 GeV (χ 1 +/ ) [Vetoing events with any τ s with p T > 20 GeV] Ture = 739 GeV (χ 40 ) Endpoint = 774 GeV Ture = 739 GeV (χ 40 ) M JW 27

28 M JW, shifting with m Hu m 1/2 -m 0 -m Hu Ωh M JW (q~ χ 1+ W+χ 10 ) M JW (q~ χ 2+ W+χ 20 τ/h) M JW (q~ χ 2+ W+χ 30 Z) 652 NAN NAN M JW (q~ χ 40 W+χ 1+ ) gluino u L, u R 1113, , , 1076 b 1, b 2 ; t 1, t 2 946, 989; 781, , 993; 787, , 1005; 787, 996 χ 1+, χ , , , 511 χ 1 0 ~ χ , 293, 316, , 328, 368, , 375, 482, Endpoint = 774 GeV Ture = 739 GeV (χ 40 ) 739 Endpoint = 856 GeV Ture = 813 GeV (χ +/ ) Endpoint = 900 GeV Ture = GeV (χ +/- 1 ) 28

29 Extraction of Model Parameters Observable Model Parameters M eff m 0, m 1/2 m 0, m 1/2, µ(m Hu ), tanβ M JW M Jττ M ττ M Jτ m 0, m 1/2, µ(m Hu ), tanβ m 0, m 1/2, µ(m Hu ), A 0, tanβ m 0, m 1/2, µ(m Hu ), A 0, tanβ In progress 29

30 A Sanity Check Random mixture of TTbar (4103 events) and Z+Jets (4081 events) with: N j > 2 with E T > 30 GeV N b > 0 with E T > 30 GeV N τ > 0 with E T > 20 GeV MET > 50 GeV Note there might be b-jets and/or τ-jets in event, but not counted as j. 30

31 Near-term Plan We are testing Mixed Event Dijet Mass (MEDM) with: Full CMS detector simulation Looks good Analyzing the data (TTbar!) Just begin Contribution to SUSY Searches LM0 W jj 31

32 SUSY Prospects with 1fb -1 95% CL exclusion-contours of the all-hadronic (3j + MET with lepton veto) searches 50% uncertainty assumed on SM background; Surpass Tevatron at ~ 50pb -1 ; No optimization of selection cuts 32

33 CMS ready! Summary SUSY with 3 rd Generations Mixed Event Dijet Mass technique to extract W jj Keep going 33

34 Backups 34

35 CMS msugra Benchmark Points 35

36 LM0 36