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Era of Discovery with CMS Detector TAMU Group Teruki Kamon , Alexei Safonov , David Toback

Era of Discovery with CMS Detector TAMU Group Teruki Kamon , Alexei Safonov , David Toback. Special Colloquium, LHC… Alexei Safonov 09/17/08 (Next Wednesday). Precision Cosmology at the Large Hadron Collider. Bhaskar Dutta Texas A&M University. Based on plenary talks at

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Era of Discovery with CMS Detector TAMU Group Teruki Kamon , Alexei Safonov , David Toback

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  1. Era of Discovery with CMS Detector TAMU Group TerukiKamon, Alexei Safonov, David Toback Special Colloquium, LHC… Alexei Safonov 09/17/08 (Next Wednesday)

  2. Precision Cosmology at the Large Hadron Collider Bhaskar Dutta Texas A&M University Based on plenary talks at Cosmo’08, IDM’08, Santa Fe’08, DM’08 11th September ’ 08

  3. LHC Days… We will try to understand: • The mechanism for generating masses • The physics behind the scale of W, Z boson mass scale • ~ electroweak scale Mplanck>>MW • Do we have any further evidence of grand unification? • The origin of dark matter Is there any particle physics connection? 4 Precision Cosmology at the LHC

  4. The Standard Model The Standard Model (SM) describes all these particles and 3 of 4 forces. We have confirmed the existence of those in the laboratory experiments. + Higgs boson Higgs has not yet been discovered The mass is constrained from LEP and Tevatron data: 114 GeV<MH<154 GeV 5 Precision Cosmology at the LHC

  5. SM problems and solutions • Solves the Higgs mass problem in a very elegant way. • Supersymmetric grand unified models include neutrinos! • Dutta, Mimura, Moahapatra, PRL 100 (2008); 96, (2006) 061801; 94, (2005) 091804; PRD 72 (2005) 075009. • Can produce correct matter-antimatter asymmtery • Dutta, Kumar, PLB 643 (2006) 284 • Can provide Inflation Dutta, Kumar, Leblond, JHEP 0707 (2007) 045; Allahverdi, Dutta and Mazumdar, PRL99 (2007) 261301., PRD (2008) to appear. What is the new model? • Can provide new sources of CP • violation, e.g., Bsy f Supersymmetry : Provides a candidate for dark matter ~ neutralino. Dutta, Mimura, PRL 97 (2006) 241802; PRD (Rapid Com) 77 (2008)051701. Goldberg’ 83; Ellis, Hagelin, Nanopoulos, Olive, Srednicki’84 • The Standard Model : • Cannot provide a dark matter candidate. • Has a serious Higgs mass divergence problem due to quantum correction. • Cannot accommodate masses for neutrinos. • Cannot provide enough matter-antimatter asymmetry. • Standard Model has fallen! 6 Precision Cosmology at the LHC

  6. Particle Physics and Cosmology Astrophysics CDM = Neutralino ( ) SUSY LHC LHC LHC SUSY is an interesting class of models to provide a weakly interacting massive neutral particle (M ~ 100 GeV). LHC 2014/8/6 7 Precision Cosmology at the LHC

  7. Supersymmetrized SM • The fundamental law(s) of nature is hypothesized to be symmetric between bosons and fermions. • Fermion Boson • Have they been observed? ➩ Not yet. 8 Precision Cosmology at the LHC

  8. SUSY Interaction Diagrams SUSY partner of W boson: chargino SUSY partner of tlepton: stau SUSY partner of Z boson: neutralino Lightest neutralinos are always in the final state! This neutralino is the dark matter candidate!! 9 Precision Cosmology at the LHC

  9. Dream of the Unification Unification scale can also be pushed to 1017-18 GeV Ameliorates Proton decay problem in the very successful SO(10) model Dutta, Mimura, Mohapatra , Phys.Rev.Lett.100:181801,2008 The grand unification of forces occur in SUSY models. ☺ U(1)Y Force U(1)Y Force 10 Precision Cosmology at the LHC

  10. Search for SUSY-upcoming days Large Hadron Collider- susy particles will be directly produced Existence of Higgs will be explored • Higgs mass in the well motivated SUSY models: < 150 GeV • Current experimental bound: 114 - 154 GeV Direct detection experiment, CDMS, Xenon 100, LUX etc Indirect detection experiments, e.g., PAMELA has already observed excess of positron excess in cosmic ray … g Fermi Gamma Ray Space Telescope: Sensitive to gamma ray from Dark Matter annihilation n e+ IceCube: Sensitive to neutrinos from DM annihilation Tevatron search for Bs m+ m- ( highest reach on SUSY masses) Arnowitt, Dutta, Kamon and Tanaka, Phys.Lett.B538 (2002) 121. 11 Precision Cosmology at the LHC

  11. SUSY at the LHC MW,MZ (or l+l-, t+t-) High energy jet [mass difference is large] DM Colored particles get produced and decay into weakly interacting stable particles The energy of jets and leptons depend on the sparticle masses which are given by models DM R-parity conserving (or l+l-, t+t-) The signal : jets + leptons + missing Energy 12 Precision Cosmology at the LHC

  12. Excess in ETmiss + Jets The heavy SUSY particle mass is measured by combining the final state particles q q q q • Excess in ETmiss + Jets  R-parity conserving SUSY • Meff Measurement of the SUSY scale at 10-20%. Since squarks and gluinos are heavier than W,Zs Hinchliffe and Paige, Phys. Rev. D 55 (1997) 5520 • ETj1>100 GeV, ETj2,3,4> 50 GeV • Meff > 400 GeV (Meff ETj1+ETj2+ETj3+ETj4+ ETmiss) • ETmiss > max [100, 0.2 Meff] Precision Cosmology at the LHC 13

  13. Relic Density and Meff SUSY scale can be measured with an accuracy of 10-20% • This measurement does not tell us whether the model can generate the right amount of dark matter • The dark matter content is measured to be 23% with an accuracy less than 4% at WMAP • Question: To what accuracy can we calculate the relic density based on the measurements at the LHC? Precision Cosmology at the LHC 14

  14. Anatomy of sann + …. Co-annihilation (CA) Process Griest, Seckel ’91 + + …. A near degeneracy occurs naturally for light stau in mSUGRA. Precision Cosmology at the LHC 15

  15. Dark Matter Allowed Region Co-annihilation Region 16 Precision Cosmology at the LHC

  16. MHiggs > 114 GeV Mchargino> 104 GeV 2.2x10-4 <B(b s g) <4.5x10-4 (g-2)m : 3 s deviation from SM Minimal Supergravity (mSUGRA) <H> = 246 GeV <Hu> b <Hd> SUSY model in the framework of unification: + Key Experimental Constraints 4 parameters + 1 sign tanb<Hu>/<Hd> at MZ m1/2 Common gaugino mass at MGUT m0 Common scalar mass at MGUT A0 Trilinear couping at MGUT sign(m) Sign of m in W(2) = m HuHd Arnowitt, Chamesdinne, Nath, PRL 49 (1982) 970; NPB 227 (1983) 121. Barbieri, Ferrara, Savoy, PLB 119 (1982) 343. Lykken, Hall, Weinberg, PRD 27 (1983) 2359. 17 Precision Cosmology at the LHC

  17. DM Allowed Regions in mSUGRA [Focus point region] the lightest neutralino has a larger Higgsino component Feng, Matchev, Wilczek, PLB482 388,2000. [A-annihilation funnel region] This appears for large values of m1/2 [Stau-Neutralino CA region] Arnowitt, Dutta, Santoso, NPB 606:59,2001. Ellis, Falk, Olive, PLB 444:367,1998. [Bulk region] is almost ruled out Overdense region Precision Cosmology at the LHC

  18. Signals of the Allowed Regions • Neutralino-stau coannihilation region: jets + taus (low energy) + missing energy [Arnowitt, Dutta, Gurrola, Kamon, Krislock, Toback, PRL, 100, (2008) 231802; Arnowitt, Dutta, Kamon, Kolev, Toback,PLB 639 (2006) 46; Arnowitt, Aurisano, Dutta, Kamon, Kolev, Simeon, Toback, Wagner; PLB 649 (2007)73] • Focus point: jets+ leptons +missing energy [Crockett, Dutta, Flanagan, Gurrola, Kamon, Kolev, VanDyke, 08; • Tovey, PPC 2007; Baer, Barger, Salughnessy, Summy, Wang , PRD, 75, 095010 (2007)] • Bulk region: jets+ leptons +missing energy [Nojiri, Polsello, Tovey’05] • Annihilation funnel: mass of pseudo scalar Higgs = 2 mass of DM • Overdense regions: Higgs+Jets, Z+jets, taus+jets+missing energy [Dutta, Gurrola, Kamon, Krislock, Lahanas, Mavromatos, Nanopoulos, arXiv:0808.1372 ] 19 Precision Cosmology at the LHC

  19. Goal for the analysis • Establish the “dark matter allowed region” signal • Measure SUSY masses • Determine mSUGRA parameters • Predict Wch2 and compare with WCDMh2 Precision Cosmology at the LHC

  20. Smoking Gun of CA Region Low energy taus exist in the CA region However, one needs to measure the model parameters to predict the dark matter content in this scenario SUSY Masses Unique kinematics 97% 100% (CDM) 2 quarks+2 t’s +missing energy 21 Precision Cosmology at the LHC

  21. Low Energyt and Mtt ETvis(true) > 20, 20 GeV Number of Counts / 1 GeV ETvis(true) > 40, 20 GeV ETvis(true) > 40, 40 GeV Arnowitt, Dutta, Kamon, Kolev, Toback PLB 639 (2006) 46 Low energy t’s are an enormous challenge for the detectors We need to involve the low energy t’s In our analysis Low energy t Precision cosmology at the LHC 22

  22. ETmiss+2t+2j Analysis We use ISAJET + PGS4 Arnowitt, Dutta, Kamon, Kolev, Toback PLB 639 (2006) 46 Precision Cosmology at the LHC

  23. OS-LS Mtt Distribution Clean peak even for low DM • First, our goal is to determine • all the masses 24 Precision Cosmology at the LHC

  24. SUSY Anatomy SUSY Masses 97% 100% (CDM) Meff Mjtt Mtt pT(t) 25 Precision Cosmology at the LHC

  25. Meff , Meff (b)Distribution • ETj1 > 100 GeV, ETj2,3,4 > 50 GeV • [No e’s, m’s with pT > 20 GeV] • Meff > 400 GeV • (Meff ETj1+ETj2+ETj3+ETj4+ ETmiss [No b jets; eb ~ 50%]) • ETmiss > max [100, 0.2 Meff] • Meff(b)> 400 GeV • (Meff(b)ETj1=b+ETj2+ETj3+ETj4+ ETmiss [j1 = b jet]) Meff(b)peak = 1026 GeV At Reference Point Meffpeak = 1274 GeV Meff(b) can be used to determine A0 and tanb Arnowitt, Dutta, Gurrola, Kamon, Krislock, Toback, PRL, 100, (2008)231802 Precision Cosmology at the LHC

  26. Observables • Sort t’s by ET (ET1 > ET2 > …) • Use OS-LS method to extract t pairs from the decays SM+SUSY Background gets reduced • Ditau invariant mass: Mtt • Jet-t-t invariant mass: Mjtt • Jet-t invariant mass: Mjt • PT of the low energy t • Meff : 4 jets +missing energy • Meff(b) : 4 jets +missing energy All these variables depend on masses  model parameters Since we are using 7 variables, we can measure the model parameters and the grand unified scale symmetry (a major ingredient of this model) 27 Precision Cosmology at the LHC

  27. Determining SUSY Masses (10 fb-1) ~ ~ Meff(b) = f7(g, qL, t, b) 7 Eqs (as functions of SUSY parameters) 1s ellipse 10 fb-1 ~ ~ Invert the equations to determine the masses Arnowitt, Dutta, Gurrola, Kamon, Krislock, Toback Phys. Rev. Lett. 100, (2008) 231802 Precision Cosmology at the LHC

  28. GUT Scale Symmetry m1/2 ~ ~ g g mass ~ ~ c c 0 0 1 1 ~ ~ c c 0 0 2 2 MGUT Log[Q] MZ We can probe the physics at the Grand unified theory (GUT) scale Use the masses measured at the LHC and evolve them to the GUT scale using mSUGRA The masses , , unify at the grand unified scale in SUGRA models Gaugino universality test at ~15% (10 fb-1) Another evidence of a symmetry at the grand unifying scale! 29 Precision Cosmology at the LHC

  29. DM Relic Density in mSUGRA ~ c 0 1 ~ c 0 2 [1] Established the CA region by detecting low energy t’s (pTvis > 20 GeV) [2] Determined SUSY masses using: Mtt, Slope, Mjtt, Mjt, Meff e.g., Peak(Mtt) = f (Mgluino, Mstau, M , M ) [3] Predict the dark matter relic density by determining m0, m1/2, tanb, and A0 [4] We can also predict the dark matter-nucleon scattering cross section but it has large theoretical error Precision Cosmology at the LHC

  30. Determining mSUGRA Parameters • Solved by inverting the following functions: 10 fb-1 Phys. Rev. Lett. 100, (2008) 231802 Direct Detection Precision Cosmology at the LHC

  31. Focus Point (FP)-II Br(g → χ20 tt) = 10.2% Br(g → χ20 uu) = 0.8% Br(g → χ30 tt) = 11.1% Br(g → χ30 uu) = 0.009% - ~ ~ - - ~ - ~ • m0 is large, m1/2 can be small, e.g., m0= 3550 GeV, m1/2=314 GeV, tanb=10, A0=0 M(gluino) = 889 GeV, ΔM(χ30- χ10) = 81 GeV, ΔM(χ20- χ10) = 59 GeV, ΔM(χ30- χ20) = 22 GeV 32 Precision Cosmology at the LHC

  32. Dilepton Mass at FP Relic density calculation depends on m, tanb and m1/2 m1/2, m and tanb can be solved from M(gluino), ΔM (χ30- χ10) and ΔM (χ20- χ10) Errors of (300 fb-1): M(gluino) 4.5% ΔM (χ30- χ10) 1.2% ΔM (χ20- χ10) 1.7% Events/GeV tanbm 22% 0.1% • Tovey, talk at PPC 2007 • Baer, Barger, Salughnessy, Summy, Wang , PRD 75, 095010 (2007) • Crockett, Dutta, Flanagan, Gurrola, Kamon, Kolev, Krislock, VanDyke (2008) Chargino masses can be measured! Work in Progress… M(ll) (GeV) 33 Precision Cosmology at the LHC

  33. Bulk Region-III ~ ~ ~ 01 g uL ~ ~ l 02 The most part of this region in mSUGRA is experimentally (Higgs mass limit, bs g) ruled out Relic density is mostly satisfied by t channel selectron, stau and sneutrino exchange Perform the end point analysis to determine the masses mSUGRA point: m0=70; A0=-300 m1/2=250; m>0; tanb=10; Nojiri, Polsello, Tovey’05 The error of relic density: 0.108 ± 0.1(stat + sys) ~ Includes: (+0.00,−0.002 )M(A); (+0.001, −0.011) tan β; (+0.002,−0.005) m(t2) [With a luminosity 300 fb-1, tt edge controlled to 1 GeV] 34 Precision Cosmology at the LHC

  34. Overdense Region-IV Overdense region (Large ): Too much dark matter m0 The final states contain Z, Higgs, staus In some models, this overdense region is not really overdense, e.g., Dilaton effect creates new parameter space Allowed region is moved up Lahanas, Mavromatos, Nanopoulos, Phys.Lett.B649:83-90,2007. 35 Precision Cosmology at the LHC

  35. Observables involving Z and Higgs • Observables: • Effective mass: Meff (peak): f1(m0,m1/2) • Effective mass with 1 b jet: Meff (b) (peak): f2(m0,m1/2, A0, tanb) • Effective mass with 2 b jets: Meff (2b) (peak): f3(m0,m1/2, A0, tanb) • Higgs plus jet invariant mass: Mbbj(end-point): f4(m0,m1/2) 4 observables => 4 mSUGRA parameters Dutta, Gurrola, Kamon, Krislock, Lahanas, Mavromatos, Nanopoulos, arXiv:0808.1372 We can solve for masses by using the end-points 36 Precision Cosmology at the LHC

  36. Determining mSUGRA Parameters • Solved by inverting the following functions: 1000 fb-1 37 Precision Cosmology at the LHC

  37. 2 tau + missing energy dominated regions: • Solved by inverting the following Observables: 500 fb-1 For 500 fb-1 of data Dutta, Gurrola, Kamon, Krislock, Lahanas, Mavromatos, Nanopoulos, arXiv:0808.1372 38 Precision Cosmology at the LHC

  38. DM Particle: Direct Detection? The measurement at the LHC will pinpoint the parameters of SUSY models. We can predict the direct detection probability of dark matter particles. µ (*) James White Complementary measurements ! detector Dark Matter particle (*)The TAMU group is one of the leading institutions in the US. 39 Precision Cosmology at the LHC

  39. Status - Direct Detection DAMA ZEPLIN CDMS XENON • Ongoing/future projects: CDMS, LUX, XENON100, ZEPLIN • Status: • DAMA group (Italy) – claims to have observed some events. • CDMS,ZEPLIN,XENON10, Cogent – dispute their claim. Rupak Mohapatra Bob Webb James White 10-8 pb Accomando, Arnowitt, Dutta, Santoso, NPB 585 (2000) 124 Close to the current sensitivity 40

  40. Conclusion • SM of particle physics has fallen. • Supersymmetry seems to be natural in the rescue act and the dark matter content of the universe can be explained in this theory. • The minimal SUGRA model is consistent with the existing experimental results. [1] LHC can probe the minimal SUGRA model directly. • All the dark matter allowed regions can be probed at the LHC • The dark matter content can be measured with an accuracy of 6% in the stau-neutralino coannihilation region • This accuracy depends on the final states [2] This analysis can be applied to any SUSY model 41 Precision Cosmology at the LHC

  41. Conclusion… [3] Direct detection experiments will simultaneously confirm the existence of these models. [4] Indirect detection experiments will also confirm the existence of SUSY models [5] Very exciting time ahead… 42 Precision Cosmology at the LHC

  42. Brahma

  43. Conclusion… All of these will be supersymmetry phenomenology/model papers 2014/8/6 44

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