Titel van de presentatie · QU1, RuG, 20/4/2011 (SdJ ) Higgs elusive, illusive, delusive Quantum...

QU1, RuG, 20/4/2011 (SdJ )

Higgselusive, illusive, delusive

Quantum Universe 1, 21 April 2011, RuG

Sijbrand de JongRadboud University Nijmegen

1

Tuesday, April 26, 2011

Intro SM

QU1, RuG, 20/4/2011 (SdJ ) 2


SM successes

QU1, RuG, 20/4/2011 (SdJ ) 3

Measurement Fit |Omeas−Ofit|/σmeas

0 1 2 3

0 1 2 3

Δαhad(mZ)Δα(5) 0.02758 ± 0.00035 0.02768mZ [GeV]mZ [GeV] 91.1875 ± 0.0021 91.1874ΓZ [GeV]ΓZ [GeV] 2.4952 ± 0.0023 2.4959σhad [nb]σ0 41.540 ± 0.037 41.479RlRl 20.767 ± 0.025 20.742AfbA0,l 0.01714 ± 0.00095 0.01645Al(Pτ)Al(Pτ) 0.1465 ± 0.0032 0.1481RbRb 0.21629 ± 0.00066 0.21579RcRc 0.1721 ± 0.0030 0.1723AfbA0,b 0.0992 ± 0.0016 0.1038AfbA0,c 0.0707 ± 0.0035 0.0742AbAb 0.923 ± 0.020 0.935AcAc 0.670 ± 0.027 0.668Al(SLD)Al(SLD) 0.1513 ± 0.0021 0.1481sin2θeffsin2θlept(Qfb) 0.2324 ± 0.0012 0.2314mW [GeV]mW [GeV] 80.399 ± 0.023 80.379ΓW [GeV]ΓW [GeV] 2.085 ± 0.042 2.092mt [GeV]mt [GeV] 173.3 ± 1.1 173.4

July 2010


QU1, RuG, 20/4/2011 (SdJ )

SM fermion masses

4

e-υe L e+R(ϕ- ϕ0)

e-υe L e+R(0 v+H)

Electroweak interaction: left handed doublets right handed singlets

split masses in doublets: Higgs doublet to connect L↔R

dynamic symmetry breaking by vacuum expectation value


QU1, RuG, 20/4/2011 (SdJ )

Weak boson cross section unitary

5

+ E2 divergente+

e-

W+

W-υ

e+

e-

W+

W-

γ

e+

e-

W+

W-

Z+ E divergent

e+

e-

W+

W-

H+ log(E) divergent

?Tuesday, April 26, 2011

QU1, RuG, 20/4/2011 (SdJ )

quantum corrections

6

fermion loop ~mf2 Higgs correction ~log(MH)

Quantum Field Theory:Everything dependson everything else

running coupling constant ⇒ running masses


!"#$%&%!'()

*+,

- . / () (0 (- (. (/

%1!"#2

34

())

(5)

0))

05)

6))

65)

%7"89:8;<9=>=9?%;+:@A

%B9<;=*=9?%;+:@A

%C=@=9"DE%F"9<G9<;=*=9?%;+:@A

%H"8+DE%F"9<G9<;=*=9?%;+:@A%"88+8%;<@AGI%J&+%9K"+8"9=L<*%"88+8G"BK+J@%<8"%(

#%M%0$

#%M%$

!"#$%&%!'()

*+,

- . / () (0 (- (. (/

%1!"#2

34

())

(5)

0))

05)

6))

65)

QU1, RuG, 20/4/2011 (SdJ )

SM Higgs boson perturbativity and stability

7

Higgs self coupling: λ(Q2)=λ(µ2)/(1-βlog(Q2/µ2) with β=12λ(µ2)/(16π2) explodes if mH>2v216π2/12log(Λ2/v2)

at small λ,top dominates in the running:∂λ/∂log(Q2)∝-mt/vλ<0 (Higgs potential unbounded from below!) ifmH2<6mt4 log(Λ2/v2)/(π2v2)

“The Probable Fate of the Standard Model”J. Ellis et al.,Phys.Lett.B679 (2009) 369


QU1, RuG, 20/4/2011 (SdJ )

SM Higgs boson properties

★ mass limited by perturbativity and stability

★ Turns up as log(MH) in quantum corrections

★ Couples proportional to mass:• preferably produced by heavy particles• decays into heaviest particles kinematically available

8


SM successes

QU1, RuG, 20/4/2011 (SdJ ) 9

!

"

#

$

%

&

'

"!!$! $!!

()*!+,-"

!"#

./0123,3 45,16(67859

!#:83*;!#

<&=

!>!#?&@#!>!!!$&

!>!#?%A#!>!!!"#

6701>*1BC*D#*38E8

F:,B59*270,5E867E9

G219*#!"! E*H.4*.II+


SM successes

QU1, RuG, 20/4/2011 (SdJ ) 10

!"#$

!"#%

!"#&

'&" '(& )""

*+,!-./"''% $"" '"""

*0,,!-./"

*1,,!-./"

2!#,34

!"

456',789,:4;

456),789,<.=70>?8,@A>.B#C

DEBF,)"'"


QU1, RuG, 20/4/2011 (SdJ )

Direct SM Higgs boson searches at LEP1989-2000

11

Energy pb-1

Z peak 162>189 GeV 2461>206 GeV 536>208 GeV 32

L3

Delphi

Aleph

Opal


OPAL detector

QU1, RuG, 20/4/2011 (SdJ ) 12

muon

electron

photon


QU1, RuG, 20/4/2011 (SdJ )

Direct SM Higgs boson production at LEP

13

Easy background

Irreduciblebackground


QU1, RuG, 20/4/2011 (SdJ )

Direct SM Higgs boson search channels at LEP

14

qq bb66%ll bb

6%

υυ bb19%

ττ qq8%


QU1, RuG, 20/4/2011 (SdJ )

Higgs boson limit combination statistical methodtest statistic (discriminator): LLR(MH) = -2 log

The observation is: LLRobs

Determine what to expect for LLR with “toy experiments”for both hypotheses: PDF(LLR | b), PDF(LLR | s+b)confidence levels: 1-CLb = p(LLR<LLRobs | b) CLs+b = p(LLR>LLRobs | s+b)

To correct for small # events beingunlikely for both hypothese,modified frequentist: CLs=CLs+b/CLb

15

p(data | s+b)p(data | b)

s+b bobs

1-CLbCLs+b


QU1, RuG, 20/4/2011 (SdJ )

Higgs boson limit from LEP statistical method

p(data | η) = ∏ (1/nk!)(ηsk+bk)nk e-(ηsk+bk) ×

∏ (ηskSk(xjk;mH)+bkBk(xjk))/(ηsk+bk;mH)

η 1 for s+b, 0 for bN number of search channelsnk number of candidates in channel kxjk (discriminating) variable(s) for candidate j in channel ksk, bk total number of signal, background events in channel kSk, Bk PDFs for (discriminating) variable(s) in signal, background

16

N

k=1

j=1

nk

Poisson statistics

discriminating variables statistics


QU1, RuG, 20/4/2011 (SdJ ) 17

-30

-20

-10

0

10

20

30

40

50

106 108 110 112 114 116 118 120

mH(GeV/c2)

-2 ln

(Q)

ObservedExpected for backgroundExpected for signal plus background

LEP


QU1, RuG, 20/4/2011 (SdJ ) 18


QU1, RuG, 20/4/2011 (SdJ ) 19


QU1, RuG, 20/4/2011 (SdJ ) 20

!

"

#

$

%

&

'

"!!$! $!!

()*!+,-"

!"#

./0123,3 45,16(67859

!#:83*;!#

<&=

!>!#?&@#!>!!!$&

!>!#?%A#!>!!!"#

6701>*1BC*D#*38E8

F:,B59*270,5E867E9

G219*#!"! E


QU1, RuG, 20/4/2011 (SdJ )

Higgs boson searches at Tevatron1989-2011

21

CDF D0 (1992)

9.55 fb-1


QU1, RuG, 20/4/2011 (SdJ )

Dzero detector

22


QU1, RuG, 20/4/2011 (SdJ )

Higgs boson searches at Tevatron

23

Higgs boson production and decay at Tevatron

pb Hard Easy


QU1, RuG, 20/4/2011 (SdJ )

SM Higgs boson search channels at Tevatron

Low Mass: WH → lυbb l=e,µ ZH → llbb l=e,µ,τ ZH → υυbb H → ττ H → γγ

High Mass: H →WW → lυlυ, µυτ(had)υ, lυ qq l=e,µ WH→WWW→ l±l±, l±l±X, l=e,µ,τ ZH →ZWW → lllX, l±l±X, l=e,µ

24


QU1, RuG, 20/4/2011 (SdJ )

Higgs boson limit derivation at Tevatron

Modified frequentist as for LEP

BUT, with nuisance parameters:Extra Gaussian constraints★ to clamp background predection to observed data★ outside the expected signal region

Checked with Bayesian method (overall 1% agreement)

25


QU1, RuG, 20/4/2011 (SdJ )

SM Higgs boson limits at Tevatron

26

Text

(GeV)H

m

100 110 120 130 140 150 160 170 180 190 200

LL

R

-5

0

5

10

15

(GeV)H

m

100 110 120 130 140 150 160 170 180 190 200

LL

R

-5

0

5

10

15

!1 ! b

LLR

!2 ! b

LLR

bLLR

s+bLLR

obsLLR

July 19, 2010

-1<L> = 5.9 fb

Tevatron RunII Preliminary


QU1, RuG, 20/4/2011 (SdJ )


27

Text

)2 (GeV/cHm130 140 150 160 170 180 190 200

95

% C

L L

imit

/ S

M

1Standard Model = 1.0

)2 (GeV/cHm130 140 150 160 170 180 190 200

95

% C

L L

imit

/ S

M

1

DØ Exclusion

-1DØ Preliminary, L=4.3-8.2 fb

SM Higgs Combination

Observed

Expected

!1!Expected

!2!Expected

March 7, 2011


QU1, RuG, 20/4/2011 (SdJ )


28


QU1, RuG, 20/4/2011 (SdJ )

SM Higgs boson prospects at Tevatron

29


QU1, RuG, 20/4/2011 (SdJ )

CDF bumpselect events withexactly 1 lepton (e,mu) with pT>20 GeVmissing ET>25 GeV andexactly 2 jets > 30 GeVPTjj>40 GeVM(l,ET)>30 GeVsimilar to WH selection,except no b-tags

30

arXiv:1104.0699v1

~4pb !


QU1, RuG, 20/4/2011 (SdJ )

Higgs boson searches at the LHC

31


QU1, RuG, 20/4/2011 (SdJ )


32

Day in 201125/02 04/03 11/03 18/03 25/03 01/04 08/04 15/04

]-1To

tal I

nteg

rate

d Lu

min

osity

[pb

0

5

10

15

20

25

30

35

Day in 201125/02 04/03 11/03 18/03 25/03 01/04 08/04 15/04

]-1To

tal I

nteg

rate

d Lu

min

osity

[pb

0

5

10

15

20

25

30

35 = 7 TeVs ATLAS Online LuminosityLHC Delivered

ATLAS Recorded

-1Total Delivered: 28.8 pb-1Total Recorded: 26.8 pb

Day in 201024/03 19/05 14/07 08/09 03/11

]-1To

tal I

nteg

rate

d Lu

min

osity

[pb

0

10

20

30

40

50

60

Day in 201024/03 19/05 14/07 08/09 03/11

]-1To

tal I

nteg

rate

d Lu

min

osity

[pb

0

10

20

30

40

50

60 = 7 TeVs ATLAS Online Luminosity

LHC Delivered

ATLAS Recorded

-1Total Delivered: 48.1 pb-1Total Recorded: 45.0 pb

2010:delivered 48 pb-1

recorded 45 pb-1


QU1, RuG, 20/4/2011 (SdJ )


33


QU1, RuG, 20/4/2011 (SdJ )


34


QU1, RuG, 20/4/2011 (SdJ )

Higgs boson prospects at the LHC

35

!"#$%&'(

)** +** ,** -** .**

/)012$3452$6!78(91:;92<=!>?

*

+

-

@

A

)*

)+

BC!D$%;!!!.

BC!D$%;!!!, !!

BC!D$%;E.F!G7!

)+* ).*

!"#!$ H4$I9(9154<!JK9(8I529:1L


QU1, RuG, 20/4/2011 (SdJ )

SM Higgs boson combining it all

36

[GeV]HM

100 150 200 250 300

2!

"

0

2

4

6

8

10

12

14

16

18

20

22

LE

P 9

5%

CL

Te

va

tro

n 9

5%

CL

#1

#2

#3

#4

= -2ln(Q)2!$Direct searches WW only. Average neglects correlations%LHC: H

Theory uncertainty

Fit including theory errors

Fit excluding theory errors

G fitter SMM

OR

11

Max Baak,Moriond 15/3/2011

115 GeV < mH < 137 GeV


QU1, RuG, 20/4/2011 (SdJ )

SM Higgs boson combining it all

37

!"#$%&%!'()

*+,

- . / () (0 (- (. (/

%1!"#2

34

())

(5)

0))

05)

6))

65)

7"89:;+<%"=>*?@A+<%9:%BC5D%EF

%G";:?;H9:A8A:I%H+?<J

%K:9HA*A:I%H+?<J

%LA<A:"M7%N":9@:9HA*A:I%H+?<J

%O";+M7%N":9@:9HA*A:I%H+?<J%";;+;%H9<J@P%Q&+%:R"+;":A>9*%";;+;@"KR+Q<%9;"%(

#%S%0$

#%S%$

!"#$%&%!'()

*+,

- . / () (0 (- (. (/

%1!"#2

34

())

(5)

0))

05)

6))

65)

FTG%"=>*?@A+<9:%BC5D%EF

We are here !


QU1, RuG, 20/4/2011 (SdJ )

Beyond SM: No Higgs

38

+ E2 divergente+

e-

W+

W-υ

e+

e-

W+

W-

γ

e+

e-

W+

W-

Z+ E divergent

!Tuesday, April 26, 2011

QU1, RuG, 20/4/2011 (SdJ )

Beyond SM: No Higgs

39

+ E2 divergente+

e-

W+

W-υ

e+

e-

W+

W-

γ

e+

e-

W+

W-

Z+ E divergent

e+

e-

W+

W-

H+ Composite Higgs

? weak: deviating Brstrong (technicolor): multihiggs production


QU1, RuG, 20/4/2011 (SdJ )

Beyond SM: No Higgs

40

+ E2 divergente+

e-

W+

W-υ

e+

e-

W+

W-

γ

e+

e-

W+

W-

Z+ E divergent

Z

W-

W’+ W’ and Z’ bosons

W’ and Z’ shouldbe discovered atLHC energy scale

?W-

Z


QU1, RuG, 20/4/2011 (SdJ )

Beyond SM: Many Higgs

41

+ E2 divergente+

e-

W+

W-υ

e+

e-

W+

W-

γ

e+

e-

W+

W-

Z+ E divergent

e+

e-

W+

W-

H+ no divergence ?

?Tuesday, April 26, 2011

QU1, RuG, 20/4/2011 (SdJ ) 42

Gauge particles

SQuarks

SLeptons

Gauginos

~ ~ ~~ ~ ~

~ ~ ~~ ~ ~

~ ~~ ~

~Higgsinofermion

hA

H±

hA

H±

~~

~ χ±1χ±

2

~~

χ02

~χ0

1~

χ04

~χ0

3~

Neutralinos

Charginos

Gluinos

MSSM:> 100 parameters

MSugra:4.5 parameters


QU1, RuG, 20/4/2011 (SdJ )

2 Higgs Doublet Model (2HDM) properties

43

h

AH±

Hϕu

0ϕu

+

ϕd0ϕd

+

Up

Down

W Zvu

vd

tan(β)=vu/vd tan(α)

lightest heaviestoften SM like(not always)

in general 2 free parameters: tan(β) & mAor tan(β) & mhor mh & mAIn MSSM more constraint


QU1, RuG, 20/4/2011 (SdJ )

SUSY 2 Higgs Doublet Model properties

44

h

AH±

Hϕu

0ϕu

+

ϕd0ϕd

+

Up

Down

W Zvu

vd

tan(β)=vu/vd tan(α)

lightest heaviestoften SM like(not always)

Higgs masses function of otherSUSY parameters:1st order mh<mZincl. higher orders mh<~140 GeVSUSY can be excluded bynot finding a light neutral Higgs


QU1, RuG, 20/4/2011 (SdJ )

SUSY Higgs searches at LEP

45

e+

e-

Z

hZ* e+

e-

A

h

e+

e-

H+

H-

Z* Z*

~sin(β-α) ~cos(β-α)


QU1, RuG, 20/4/2011 (SdJ )

SUSY Higgs limits from Tevatron

46

b b

h,A~tan2(β)

for large tan2(β)similar h and A production

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--

89):;<&<#=>#?8@

A=B&CD&<#:E+E189F&)1&<#:E+E1

"#,#!89F&)1&<#:E+E1#

"#"#!89F&)1&<#:E+E1#

GH"--#%&'###+29I#J+

#H,K&D21CL3#M;3#NN#@C&:E+E32C>I#?G#,O0H"O"#P=

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--

89):;<&<#=>#?8@

A=B&CD&<#:E+E189F&)1&<#:E+E1

"#,#!89F&)1&<#:E+E1#

"#"#!89F&)1&<#:E+E1#

GH"--#%&'##3I#+E9E3JK#

#H,L&D21CI3#M;3#NN#@C&:E+E32C>K#?G#,O0H"O"#P=

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--

89):;<&<#=>#?8@

A=B&CD&<#:E+E189F&)1&<#:E+E1

"#,#!89F&)1&<#:E+E1#

"#"#!89F&)1&<#:E+E1#

GH"--#%&'##+29I#J+

#K,L&D21CM3#N;3#OO#@C&:E+E32C>I#?G#,P0K"P"#Q=

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--

89):;<&<#=>#?8@

A=B&CD&<#:E+E189F&)1&<#:E+E1

"#,#!89F&)1&<#:E+E1#

"#"#!89F&)1&<#:E+E1#

GH"--#%&'#3I#+E9E3JK#

#L,M&D21CI3#N;3#OO#@C&:E+E32C>K#?G#,P0L"P"#Q=

!"#$%&'()*+,-- ,"- ,.- ,/- ,0- "--

!123

,-

"-

4-

.-

5-

/-

6-

0-

7-

,--


QU1, RuG, 20/4/2011 (SdJ )

SUSY Higgs: beware non SM behaviourFermiofobic Higgs: H→γγ

47

!"#$%&'(

)*++ *+, **+ **, *-+ *-, *.+ *., */+ */, *,+

&!"'0&

!!" '

!12"(

#!$

*

*+

-*+

304$56$7!89:9;<=>$?;$7!89:9;

@83!>5$79?;9AB

!*!4C7C!<=>$?;$7!89:9;!!-!4C7C!<=>$?;$7!89:9;!

D*EF!>5$G9:9BH5IJ!KC-!'0


QU1, RuG, 20/4/2011 (SdJ )48

But acceleration not nearlyas big as SM predicts !

VEV inexpanding

space ?


QU1, RuG, 20/4/2011 (SdJ )

Canonical Quantization ⇔ Path Integral ?

49

V(ϕ)

µ2<0λ>0

-v +v

ϕ

Expandaroundminimum


QU1, RuG, 20/4/2011 (SdJ ) 50

Expanding around classical minimum gives:complex and non-convex effective potential (=sum 1PI Greenʼs functions)

In general effective potential must be convex(Symanzik & Iliopoulos et al. & Haymaker et al.)

For path integral approach:

this is indeed the case,and there is a huge discrepancy with canonical quantization !

Euclidean lattice calculations conform this picture (G.-J. Besjes, MSc thesis)

∫Dφ φ eiS(φ)/ħ

∫Dφ eiS(φ)/ħ<vac|φ|vac>=

IMAPP: Ronald Kleiss & collaborators


What if:

QU1, RuG, 20/4/2011 (SdJ ) 51


QU1, RuG, 20/4/2011 (SdJ )

Canonical Quantization ⇔ Path Integral !

52

V(ϕ)

µ2<0λ>0

-v +v

ϕ

ConvexEffectivePotentialsolves:- vacuum expansion problem- part of dark energy problem Phenomenological

implications???


QU1, RuG, 20/4/2011 (SdJ )

Higgs and non commutative geometry(Chamseddine, Connes, Marcolli)

spectral triple: A matrices on H Hilbert space of spinors L2(M,S)⊗Mn(C) D Dirac operator on H: γµ∂µ Spectral action: count number of states of D on H up to cut-off ΛSΛ(D) = ∑fk ak(D2/Λ2) = (Λ2)2 f0 (1/4π2) ∫M √g dx + Λ2 f2 (1/4π2) (1/12) ∫M R√g dx + f4 (1/4π2) (1/360) ∫M [Rµ;µ +(5/4)R2-2RµνRµν-(7/4)RµνρσRµνρσ√g dx + ...

Local symmetries incorporated by D → DA=D+a[D,b], a,b∈ A

53

IMAPP: Walter van Suijlekom

& collaborators

Einstein-Hilbert Action if Λ2f2/24π2=1/8πG ⇒ Λ ~ Plank energy


QU1, RuG, 20/4/2011 (SdJ )

Higgs and non commutative geometry

Standard Model: A= C ⊕ H ⊕ M3(C) (cf. U(1)⊗SU(2)⊗SU(3))

(btw: A= C ⊕ H ⊕ H ⊕ M3(C) gives also υmaj see-saw mass terms)relations between couplings: g3

2=g22=(5/3)g1

2 , g32f0=π2/2

Note: NO unification !

predicts Higgs mass at 168 GeV

Now attempting to include SUSY...54

IMAPP: Walter van Suijlekom

& collaboratorsII I

I I I I


QU1, RuG, 20/4/2011 (SdJ ) 55

Higgs

elusive: Yes, but probably not for much longer

illusive: Probably not

delusive: There is reason to be suspicious


QU1, RuG, 20/4/2011 (SdJ ) 56


QU1, RuG, 20/4/2011 (SdJ ) 57


Titel van de presentatie · QU1, RuG, 20/4/2011 (SdJ ) Higgs elusive, illusive, delusive Quantum...

Documents

Transcript of Titel van de presentatie · QU1, RuG, 20/4/2011 (SdJ ) Higgs elusive, illusive, delusive Quantum...