LHC/ILC. Hitoshi Murayama (Berkeley) SLAC SSI, 7/27/2006

Transcription

1 LHC/ILC Hitoshi Murayama (Berkeley) SLAC SSI, 7/27/2006

2 Technicolor Lykken: It doesn t look good but is not going away 2

3 LHC/ILC Hitoshi Murayama (Berkeley) SLAC SSI, 7/27/2006

4 Outline e + e - Linear Collider Reconstruction of the Lagrangian mass, spin, quantum numbers, mixing, couplings use supersymmetry as an example Physics Significance 4

5 e + e - Linear Collider

6 Large Hadron Collider (LHC) proton-proton collider 14TeV energy (cf. Fermilab) Under construction at CERN, Geneva Turn on in 2007 Finally reaching the energy Fermi told us about in 1933! 6

7 CMS

8 Higgs at ATLAS Robust discovery Signal significance H tth (H bb) H ZZ (*) 4l H WW (*) ll qqh qqww (*) qqh qq Total significance Ldt = 30 fb 1 (no K-factors) ATLAS m H (GeV/c 2 )

9 Supersymmetry Tevatron/LHC will discover Can do many precision measurements at LHC m 1/2 (GeV) CMS TH h 2 = 0.4 h 2 = 1 g(3000) ~ miss E T (100 fb -1 ) q(2000) ~ q(1500) ~ g(1500) ~ L dt = 1, 10, 100, 300 fb -1 A 0 = 0, tan = 35, μ > 0 miss E T (300 fb -1 ) g(2000) ~ miss E T (10 fb -1 ) miss E T (1 fb -1 ) g(1000) ~ h(123) g(2500) ~ q(2500) ~ one one one M l (GeV) R O1 S5 one 200 q(500) ~ h(110) EX h 2 = 0.15 g(500) ~ q(1000) ~ cosmologically plausible region Fermilab reach: < 500 GeV M 0 (GeV) (GeV) m 0 9

10 New physics looks alike b _ b t W W W b W q _ q l l _ b l l q _ q 4th generation missing ET, multiple jets, b-jets, (like-sign) leptons g~ g~ g~ q~ ~ b ~ q W _ q b ~ _ b SUSY W l ~ l l l 0 ~ l l 0 P 8 0 P 8 0 P 8 0 t _ t t _ t W b b W _ b W W _ b technicolor +Universal extra dimension, little Higgs with T-parity 10 l q l _ l q q _ q l

11 11

12 Task Why do we live in a cosmic superconductor? We can eliminate many possibilities at LHC But new interpretations necessarily emerge Race will be on: theorists coming up with new interpretations experimentalists excluding new interpretations A loooong process of elimination Crucial information is in details Reconstruct the theory from measurements 12

13 Need absolute confidence As an example, supersymmetry New-York Times level confidence still a long way to Halliday-Resnick level confidence We have learned that all particles we observe have unique partners of different spin and statistics, called superpartners, that make our theory of elementary particles valid to small distances. 13

14 Electron-positron collider e, e + point-like with no structure Well-understood environment Linear instead of ring to avoid synchrotron loss Super-high-tech machine Accelerate the beam over >15km Focus beam down to a few nanometers and make them collide International Linear Collider (ILC) electron sources (HEP and x-ray laser) linear accelerator 33 km x-ray laser linear accelerator damping ring positron preaccelerator electron-positron collision high energy physics experiments positron source aux. positron and 2nd electron source damping ring e - e + e - Linear Collider 14

15 ILC elementary particles well-defined energy, angular momentum LHC p p uses its full energy can produce particles democratically can capture nearly full information ILC e + e - 15

16 LHC vs ILC (oversimplified) 16

17 Polarized beams serves as two different machines e + e R - e + e L - 17

18 Polarized beams serves as two (nine?) different machines e L + e R - e R + e L - e L + e L - e R + e R - e - e L - e R - e L - e L - e R - e R - 18

19 Polarized beams e L and e R are really different particles at E>>m Z 19

20 Reconstruct Lagrangian from data Specify the fields mass spin Klein-Gordon, Dirac, Majorana, gauge SU(3)xSU(2)xU(1) quantum numbers mixing of states Specify their interactions SU(3)xSU(2)xU(1) quantum numbers determine gauge interactions Yukawa couplings 20

21 Reconstruct Lagrangian from data Specify the fields mass spin Klein-Gordon, Dirac, Majorana, gauge SU(3)xSU(2)xU(1) quantum numbers mixing of states Specify their interactions SU(3)xSU(2)xU(1) quantum numbers determine gauge interactions Yukawa couplings 21

22 mass

23 EPH 23

24 Two-body kinematics In the CM frame of two particles of mass m 1 and m 2 ( ) s E 1 = 1 + m2 1 2 s m2 2 s ( ) s E 2 = 1 + m2 2 2 s m2 1 s s p 1 = p 2 = 2 1 2(m2 1 + m2 2 ) s + (m2 1 m2 2 )2 s 2 24

25 ~ 0 In the smuon rest frame In the lab frame γ µ = E µ m µ = ˆp µ = m µ 2 s 2m µ muon momentum in the lab frame p µ = m µ 2 ( ) 1 m2 χ 0 m 0 µ Therefore, the muon energy is ( ) ( s 1 m2 χ 0 s 4 m 0 µ (1 β µ ) < E µ < 4 dσ de µ ( ) 1 m2 χ 0 (1,sin ˆθ,0,cos ˆθ) β µ = m 2 µ 1 4m2 µ s (γ µ + γ µ β µ cos ˆθ,sin ˆθ,0,γ µ cos ˆθ + γ µ β µ ) 1 m2 χ 0 m 0 µ dσ d cos ˆθ = constant 25 ) (1 + β µ ) dd E

26 ~ W W E miss ~ ~ R R lepton energy E l [GeV] fit to the kinetic distribution m µ = ± 0.3 GeV m χ 0 = 71.9 ± 0.1 GeV

27 LHC/LC synergy

28 Reconstruct Lagrangian from data Specify the fields mass spin Klein-Gordon, Dirac, Majorana, gauge SU(3)xSU(2)xU(1) quantum numbers mixing of states Specify their interactions SU(3)xSU(2)xU(1) quantum numbers determine gauge interactions Yukawa couplings 28

29 Spin

30 Spin production angle distribution well above the threshold: spin 1/2 (1+cos) 2 spin 0 sin 2 30

31 ALEPH DALI Run=15768 Evt=5906

32 New particle has spin 1/2 (1+cos) 2 1+cos 2 (1-cos) 2 sin 2 32

33 ALEPH DALI Run=9063 Evt=7848

34 New particle has spin ALEPH N/N 3jets Corrected Data 1992 Vector Gluon, LO Vector Gluon, LO + Fragment. Scalar Gluon, LO Scalar Gluon, LO + Fragment Z(x 2 -x 3 )/

35 EPH 35

36 Smuon production e + e µ + µ (µ + χ 0 1)(µ χ 0 1) once masses known, you can solve kinematics up to a two-fold ambiguity muon momenta measured: p µ 1,2 =(E 1,2, p 1,2 ) ) neutralino momenta: neutralino mass constraint: smuon mass constraint: momentum conservation: Now know Know q 1 up to a two-fold ambiguity 36 ( q µ s 1,2 = 2 E 1,2, q 1,2 ( ) 2 s q 2 1,2 = 2 E 1,2 m 2 χ ( ) 2 s ( p 1 + q 1 ) 2 = m 2 µ p 1 q 1 q 2 2 =( p 1 + p 2 + q 1 ) 2 =( p 1 + p 2 ) 2 + q p 1 q p 2 q 1 p 2 q 1 q 1, p 1 q 1, p 2 q 1 2

37 Smuon has spin 0 ~ ~ R R (1+cos) 2 false solution cos R ~ sin 2 37

38 Spin threshold behavior non-relativistic limit: L, S separately conserved S-wave m=100 GeV spin 1/2 spin 0 P-wave E CM 38 m µ = ± 0.09 GeV m χ 0 = 71.9 ± 0.05 GeV

39 Reconstruct Lagrangian from data Specify the fields mass spin Klein-Gordon, Dirac, Majorana, gauge SU(3)xSU(2)xU(1) quantum numbers mixing of states Specify their interactions SU(3)xSU(2)xU(1) quantum numbers determine gauge interactions Yukawa couplings 39

40 gauge quantum numbers

41 polarization Use polarized electron beam can ignore m Z2 s e R couples only to B e L couples to B +W 0 e R e B f _ f (g 2 Y f ) 2 e L f B +W 41 e _ f (g 2 Y f +g 2 I 3f ) 2 /4

42 Reconstruct Lagrangian from data Specify the fields mass spin Klein-Gordon, Dirac, Majorana, gauge SU(3)xSU(2)xU(1) quantum numbers mixing of states Specify their interactions SU(3)xSU(2)xU(1) quantum numbers determine gauge interactions Yukawa couplings 42

43 Disentangle mixings

44 gauginos, higgsinos charged ones charginos ( )( ) ( W H d ) M 2 2mW sinβ W + 2mW cosβ µ neutral ones neutralinos M 1 0 m Z s W c β m Z s W s β ( B, W 0, H d, 0 H u) 0 0 M 2 m Z c W c β m Z c W s β m Z s W c β m Z c W c β 0 µ m Z s W s β m Z c W s β µ 0 H + u B W 0 H d 0 H u 0 44

45 e + e χ + 1 χ 1 ( χ 0 1l ± ν l )( χ 0 1q q ) 45

46 e + e χ 0 2 χ 0 2 ( χ 0 1l + l )( χ 0 1l + l ) 46

47 Model-independent parameter determination e + e - L/R /Z s-channel Chargino/neutralino mass matrices have four parameters M 1, M 2,, tan Can measure 2+4 masses can measure 10x2 neutralino cross sections can measure 3x2 chargino cross sections depend on masses of ν e, ẽ L, ẽ R e input fit + ~ + 1 ~ - 1 σ L,R (e + e χ 0 i χ 0 j) σ L,R (e + e χ + i χ j ) + e - R ~ e t-channel ~ + 1 ~ - 1 M GeV 152 ±1.8 GeV µ 316 GeV 316 ±0.9 GeV tan β 3 3 ±0.7 M GeV 78.7 ±0.7 GeV 47

48 Stop ( m ( t L t R) 2 Q 3 + mt 2 (A t µ ) cotβ)m t )( t L (At µcotβ)m t m 2 t + m2 t t R a) b) cos t ~ R - R R + R L + L polarization e - /e + 0.8/0.6 L - L m(stop) (GeV) cos t ~ m h = 115 GeV, m t1 LHC TESLA GigaZ m t2 ~ = 180 GeV M A = 257 GeV, tan > 10 direct measurement ~ [GeV] at TESLA

49 Reconstruct Lagrangian from data Specify the fields mass spin Klein-Gordon, Dirac, Majorana, gauge SU(3)xSU(2)xU(1) quantum numbers mixing of states Specify their interactions SU(3)xSU(2)xU(1) quantum numbers determine gauge interactions Yukawa couplings 49

50 Interaction

51 Feynman rules Single gauge coupling constant gives all of these Feynman vertices f A g ÿg T a T a f f ~ f ~ f ~ f D a g 2 ~ f ~ f 51

52 selectron production e + ~ l + R e + ~ e + R /Z + 4 i=1 ~ 0 i e - L/R l=e,, ~ l - R e - R ~ e - R s-channel t-channel Fig.1 M sinθ [ 1 4Y 2 B 1 2cosθβ f + β 2 f + 4M2 1 /s 52 ] Y B = g e R ẽ R B 2 g

53 gaugino coupling 1.2 ILC ratio of couplings e B = B ~ e supersymmetry e e~ rate and angular distribution of selectron production kinematic fit and threshold scans mass of the bino 53

54 Reconstruct Lagrangian from data Specify the fields mass spin Klein-Gordon, Dirac, Majorana, gauge SU(3)xSU(2)xU(1) quantum numbers mixing of states Specify their interactions SU(3)xSU(2)xU(1) quantum numbers determine gauge interactions Yukawa couplings 54

55 Proof of supersymmetry This way, you can show: new particle has the same gauge quantum numbers as one of the SM particle their spins differ by 1/2 it has a Yukawa coupling whose size is 2 times the known gauge coupling You have reconstructed the supersymmetric Lagrangian from data! 55

56 Need absolute confidence As an example, supersymmetry New-York Times level confidence still a long way to Halliday-Resnick level confidence We have learned that all particles we observe have unique partners of different spin and statistics, called superpartners, that make our theory of elementary particles valid to small distances. 56

57 Physics Significance

58 Prove Higgs coupling mass Branching Fractions test the relation coupling mass proves that Higgs Boson is the Mother of Mass SM Higgs Branching Ratio ÿ ÿ ÿ ÿ bb + - gg cc + - W W ÿÿÿ (GeV) M H ÿÿÿÿ

59 Prove it is condensed ZH final state Prove the ZZH vertex e + Z e Z

60 Prove it is condensed ZH final state Prove the ZZH vertex We know Z:gauge boson, H: scalar boson only two types of vertices e + e Z Z Z Z Z

61 Prove it is condensed ZH final state Prove the ZZH vertex We know Z:gauge boson, H: scalar boson only two types of vertices Need a condensate to get ZZH vertex proves it is condensed in Universe HM, hep-ex/ Z e + e Z Z Z Z

62 Prove it is condensed ZH final state Prove the ZZH vertex We know Z:gauge boson, H: scalar boson only two types of vertices Need a condensate to get ZZH vertex proves it is condensed in Universe HM, hep-ex/ Z e + e Z Z Z Z m Z 2

63 Producing Dark Matter in the laboratory Collision of high-energy particles mimic Big Bang We hope to create Dark Matter particles in the laboratory Look for events where energy and momenta are unbalanced missing energy E miss Something is escaping the detector electrically neutral, weakly interacting Dark Matter!? 500cm 0 Y 500cm 4.8Gev EC 19.Gev HC 500cm 0 X 500cm YX hist.of BA.+E.C.

64 Dark Matter ÿÿÿ ÿ ÿ ÿ ÿÿÿÿÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿÿÿÿ ÿ ÿ ÿÿ ÿ ÿÿ 64

65 Extra D e measure the number of dimensions location of the wave functions e G G / (fb) LC D=10 D=9 D=8 D=7 D= E CM (GeV) ÿÿ ÿÿÿÿ ÿ ÿ ÿ ÿ ÿ 65 ÿÿ ÿÿÿÿ

66 Unification Do the forces and matter unify? We know coupling constants appear to unify with supersymmetry gaugino masses scalar masses 1/M i [GeV -1 ] 2 M j ~ [10 3 GeV 2 ] Q [GeV] Q [GeV] 66

67 Implications There is indeed unification! No gauge non-singlet particles below GeV Neutrino mass must come from gauge singlet exchange (i.e. seesaw!) Constraints on baryogenesis models (strong preference to leptogenesis by R ), axion models Buckley, HM 67

68 New force: Z ÿÿÿÿ ÿ ÿÿÿÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿ ÿÿ ~1/2 event/bin/fb -1 What kind of force? v' l s = 0.8 TeV, m Z' = 1.5 TeV s = 0.8 TeV, m Z' = 2.0 TeV s = 0.5 TeV, m Z' = 1.5 TeV s = 1.0 TeV, m Z' = 3.0 TeV a' l E 6 SO(10) LR LR 68

69 Einstein s Telescope With both LHC and ILC, we hope to see way beyond the energy scale we can probe directly, i.e. GUT and string scales 69