[PPT] - Higgs and Beyond at the LHC Selected topics mostly on Higgs physics PowerPoint Presentation

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Higgs and Beyond at the LHC

Marumi Kado Laboratoire de l’Accélérateur Linéaire Orsay (France)

Selected topics mostly on Higgs physics at the LHC, some comments about Run 2

Seminario del Dipartimento di Fisica dell’Università di Pisa (21/10/2014)

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‐ The LHC physics program is incredibly vast! ‐ This talk will mostly be centered on Higgs physics but will not cover all aspects of Higgs physics ‐ We have not fully done our home work for Run 2 projections (we have Run 3 and HL‐LHC) !

Preliminary remarks and Disclaimer

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The Run 1 of the LHC has been extremely productive … and successful!

Conference Notes Papers

Similar numbers for CMS Similar numbers for CMS

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‐ The celebrated discovery of the Higgs boson ! ‐ And nothing else…

The two main outcomes of the LHC (so far)

(surprise despite the absence of deviations in precision EW and flavor measurement)

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[GeV]

H

m

110 115 120 125 130 135 140 145 150

Local p

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10 1 10  1  2  3  4  5  6  6  7 HCP/Council 2012 CMS Prel. [24] ATLAS Prel. [23]

7 and 8 TeV

1

25 fb  Ldt

 Local p

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10 1 10 Council/ICHEP 07/2012 CMS Prel. [23] ATLAS Prel. [22]  1  2  3  4  5  6

7 and 8 TeV

1

10 fb  Ldt

 Local p

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10 1 10 Spring 2012 CMS [25] ATLAS Prel. [28]  1  2  3  4  5  6

= 7 TeV s

1

5 fb  Ldt

 Local p

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10 1 10 Summer 07/2011 CMS Prel. [20] ATLAS Prel. [21]  1  2  3  4  5  6

= 7 TeV s

1

1 fb  Ldt



A Textbook and Timely Discovery

Summer 2011: EPS and Lepton‐Photon

First (and last) focus on limits (scrutiny of the p0)

December 2011: CERN Council

First hints

Summer 2012: CERN Council and ICHEP

Discovery!

December 2012: CERN Council

Begining of a new era

5

PDG, review of Particle Physics

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8 October 2013

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2013 to François Englert and Peter Higgs  

“for the theoretical discovery

f

a mechanism that contributes to

ur

understanding

f

the

rigin
f

mass

f

subatomic particles, and which recently was confirmed through the discovery

f

the predicted fundamental particle, by the ATLAS and CMS experiments at CERN’s Large Hadron Collider”

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8 October 2013

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2013 to François Englert and Peter Higgs  

“for the theoretical discovery

f

a mechanism that contributes to

ur

understanding

f

the

rigin
f

mass

f

subatomic particles, and which recently was confirmed through the discovery

f

the predicted fundamental particle, by the ATLAS and CMS experiments at CERN’s Large Hadron Collider”

ATLAS CMS LHC

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Years of Design, Construction and Commissioning of the LHC

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Years of Design, Construction and Commissioning of Experiments

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Latin American Workshop on HEP

20 Years, projecting, constructing and Simulating…

10

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Latin American Workshop on HEP

4  event … Standard EW only or Higgs?

2011

7 TeV

11

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ATLAS CMS

ALICE LHCb

Center-of-Mass Energy (2010-2011)

7 TeV

Center-of-Mass Energy (Nominal)

14 TeV ?

Center-of-Mass Energy (2012)

8 TeV

Center-of-Mass Energy (close to nominal)

13TeV

12

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Event taken at random (filled) bunch crossings

First LHC Run Completed

Parameter 2010 2011 2012 Nominal C.O.M Energy 7 TeV 7 TeV 8 TeV 14 TeV Bunch spacing / k 150 ns / 368 50 ns / 1380 50 ns /1380 25 ns /2808  (mm rad) 2.4-4 1.9-2.3 2.5 3.75 * (m) 3.5 1.5-1 0.6 0.55 L (cm-2s-1) 2x1032 3.3x1033 ~7x1033 1034

… in LS1

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O(2) Pile‐up events

2010 2011

150 ns inter‐bunch spacing Event taken at random (filled) bunch crossings Month in Year Jan Apr Jul Oct ]

1

Delivered Luminosity [fb 5 10 15 20 25 30 35

= 7 TeV s 2010 pp = 7 TeV s 2011 pp = 8 TeV s 2012 pp

ATLAS Online Luminosity

O(10) Pile‐up events

2011

50 ns inter‐bunch spacing

O(20) Pile‐up events

2012

50 ns inter‐bunch spacing Event taken at random (filled) bunch crossings

2012 23 fb-1 at 8 TeV 2011 5.6 fb-1 at 7 TeV 2010 0.05 fb‐1 at 7 TeV 4th July seminar and ICHEP Design value (expected to be reached at L=1034 !) 14

The first LHC run

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Detector Challenges (Highlights)

‐ Trigger Challenge : How to select 400 out of 20M events per second while keeping the interesting (including unknown) physics ‐ Computing Challenge : How to reconstruct, store and distribute 400 increasingly complex events per second and their simulation (over 100 PB per experiment) ‐ Analysis Challenge : Maintain high (and as much as possible stable) reconstruction and identification efficiency for physics objects (e, , , jets, ET

mis, b‐jets) up to the

highest pile‐up

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The ugly Higgs sector

+ Dark matter ? + BSM ?

The elegant gauge sector

The Standard Model

With one doublet of complex scalar field

Non universal interactions not

governed by a symmetry

Bares most of the free

parameters of the SM

… but testable!

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(and masses of fermions)

~6 orders of magnitude Neutrinos are not even on the scale!

Not explaining the flavor Hierarchy

Replacing mass terms by Yukawa couplings

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Proof of condensate !

(and masses of fermions) (and masses of gauge bosons)

The Gift of Nature at 125 GeV

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Proof of condensate !

(and masses of fermions) (and masses of gauge bosons)

V()  2*  (*)2 v    2 

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F . Wilczek at the LEP Celebration : The Higgs mechanism is corroborated at 75%

The discovery did not exactly come as a surprise!

Prediction of the Model

MW M Z   g2 g2   g 2  cos2W

Protected by cutsodial symmetry

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The Higgs and the No Loose theorem* at the LHC

Does not preserve perturbative unitarity. Introducing a Higgs boson ensures the unitarity of this process PROVIDED that its mass be smaller than :

~ 1 TeV The longitudinally polarized amplitude of:

*approximate No Loose theorem Still very important to check : Just starting…

Overall same sign WW
4.5 s observed (3.4 s exp.)
Still a long way to go to precisely

test polarized VBS

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The mass did not exactly come as a surprise either!

Precision EW data

m

H ~ 90GeV

r  log(m

H

m

W

)

Is there a Higgs?

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Why “nothing else” came as a fundamental observation and a surprise?

The Hierarchy Problem, Naturalness and fine tuning

The Higgs potential is fully renormalizable, but…

Not really a problem unless there is a scale L ! …are quadratically divergent : Loop corrections to the Higgs boson mass…

m

H m

0 m...

(R. Barbieri)

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Possible Solutions

1.- Elegant: Mechanisms that protect the Higgs boson mass

Supersymmetry
Composite Higgs, Higgs as a pseudo goldstone boson
Large extra dimensions

2.- The multiverse and accepting fine tuning:

The anthropic principle
Near criticality of our universe

(metastable vacuum)

All more or less in trouble (G. Altarelli)

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Nothing Else (1)

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Nothing Else (2)

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Landscape Redefined

Flurry of new ideas !

Precision

‐ Mass and width ‐ Coupling properties ‐ Quantum numbers (Spin, CP) ‐ Differential cross sections ‐ Off Shell couplings and width ‐ Interferometry

Is the SM minimal?

‐ 2 HDM searches ‐ MSSM, NMSSM searches ‐ Doubly charged Higgs bosons

Tool for discovery

‐ Portal to DM (invisible Higgs) ‐ Portal to hidden sectors ‐ Portal to BSM physics with H0 in the final state (ZH0, WH0, H0H0)

Rare decays

‐ Z ‐ Muons  ‐ LFV , e ‐ JZWD etc…

…and More!

‐ FCNC top decays ‐ Di‐Higgs production ‐ Trilinear couplings prospects ‐ Etc…

One of the first goals : focus our efforts to extract most of the physical content of our data!

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QCD

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QCD

Testing predictions over 8 orders of magnitude !

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EW

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[ p b ]

t o t

 P r o d u c t i o n C r o s s S e c t i o n ,

1

10 1 10

2

10

3

10

4

10

5

10

CMS

July 2013

W

1j  2j  3j  4j 

Z

1j  2j  3j  4j 

> 30 GeV

jet T

E | < 2.4

jet

 |

 W

> 15 GeV

 T

E ,l) > 0.7  R( 

 Z

WW+WZ WW

WZ ZZ

 WV

1

36, 19 pb

1

5.0 fb

1

5.0 fb

1

4.9 fb

1

3.5 fb

1

4.9 fb

1

19.6 fb

1

19.3 fb

JHEP 10 132 (2011) JHEP 01 010 (2012) SMP-12-011 (W/Z 8 TeV) EWK-11-009 EPJC C13 2283 (2013) (WV) SMP-12-006 (WZ), 12-005 (WW7), 13-005(ZZ8) JHEP 1301 063 (2013) (ZZ7), PLB 721 190 (2013) (WW8) SMP-013-009

CMS 95%CL limit 7 TeV CMS measurement 8 TeV CMS measurement 7 TeV Theory prediction 8 TeV Theory prediction

Overview of Cross Sections

Expected Standard Model and Higgs Productions

Theory and simulation “Next-to…” (r)evolution :

NNLO PDFs sets
Calculations at unprecedented order in perturbation theory
Parton Shower (and Matrix Element matching) improvements

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[ p b ]

t o t

 P r o d u c t i o n C r o s s S e c t i o n ,

1

10 1 10

2

10

3

10

4

10

5

10

CMS

July 2013

W

1j  2j  3j  4j 

Z

1j  2j  3j  4j 

> 30 GeV

jet T

E | < 2.4

jet

 |

 W

> 15 GeV

 T

E ,l) > 0.7  R( 

 Z

WW+WZ WW

WZ ZZ

 WV

1

36, 19 pb

1

5.0 fb

1

5.0 fb

1

4.9 fb

1

3.5 fb

1

4.9 fb

1

19.6 fb

1

19.3 fb

JHEP 10 132 (2011) JHEP 01 010 (2012) SMP-12-011 (W/Z 8 TeV) EWK-11-009 EPJC C13 2283 (2013) (WV) SMP-12-006 (WZ), 12-005 (WW7), 13-005(ZZ8) JHEP 1301 063 (2013) (ZZ7), PLB 721 190 (2013) (WW8) SMP-013-009

CMS 95%CL limit 7 TeV CMS measurement 8 TeV CMS measurement 7 TeV Theory prediction 8 TeV Theory prediction

Overview of Cross Sections

Expected Standard Model and Higgs Productions

Theory and simulation “Next-to…” (r)evolution :

NNLO PDFs sets
Calculations at unprecedented order in perturbation theory
Parton Shower (and Matrix Element matching) improvements

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Higgs Production Modes

[TeV] s 7 8 9 10 11 12 13 14 H+X) [pb]  (pp 

1

10 1 10

2

10

LHC HIGGS XS WG 2013 H ( N N L O + N N L L Q C D + N L O E W )  p p H ( N N L O Q C D + N L O E W ) q q  p p WH (NNLO QCD + NLO EW)  pp ZH (NNLO QCD + NLO EW)  pp H ( N L O Q C D ) t t  p p

g g H W, Z W, Z q q H g g t t H q q q q (b) H

Gluon fusion process Vector Boson Fusion W and Z Associated Production NNnLO ~O(10%)

Two forward jets and a large rapidity gap

NLO TH uncertainty ~O(5%) NNLO TH uncertainty ~O(5%) Top Assoc. Prod. ~0.5 M events produced ~40 k events produced ~20 k events produced ~3 k evts produced tH B-quark Assoc. Prod.

 for mH = 125.5 GeV

~5 k evts produced

33

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Higgs Decay Channels

[GeV]

H

M

120 121 122 123 124 125 126 127 128 129 130

Higgs BR + Total Uncert

4

10

3

10

2

10

1

10 1

LHC HIGGS XS WG 2013

b b     c c gg   ZZ WW  Z

Dominant: bb (57%)
channel (6.3%)
The channel (0.2%)
WW channel (22%)
ZZ channel (3%)
The channel (0.02%)
cc channel (3%)

Extremely difficult

The Z (0.2%)

34

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Panorama of Higgs Analyses

Channel categories ggF VBF VH ttH  ✓ ✓ ✓ ✓ ZZ (llll) ✓ ✓ ✓ WW (ll) ✓ ✓ ✓ ✓  ✓ ✓ ✓ ✓ bb

✓

✓ ✓ Z and  ✓

✓

 ✓

✓

Invisible ✓

✓ ✓ ✓ (1408.011)

g g H W, Z W, Z q q H g g t t H q q q q (b) H

SLIDE 36

H  

The diphoton decay channel

(covers all production modes)

‐ s/b ratio ranging from few % to approximately 30% ‐ Excellent mass resolution

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H  4e

Four Lepton decay channel

(covers most production modes)

‐ High s/b ratio starting from approximately 1.5 and reaching more than 10. ‐ Excellent mass resolution

SLIDE 38

H  4l Update H  4l Single Highest Purity Candidate Event (2e2)

SLIDE 39

H  WW(*) l l

(covers most production modes)

‐ Intricate analysis ‐ Moderate s/b ratio starting from approximately 1.5 and reaching more than 10. ‐ Poor mass resolution

SLIDE 40

(Mostly) VBF H  ττ

[GeV]

 

m

100 200 300

[1/GeV]

 

S / (S+B) Weighted dN/dm

500 1000 1500 2000 2500

   SM H(125 GeV) Observed    Z t t Electroweak QCD

[GeV]

 

m

100 200 300

40
20

20 40    SM H(125 GeV) Data - background

Bkg. uncertainty

at 8 TeV

1

at 7 TeV, 19.7 fb

1

CMS, 4.9 fb

 , e

h



h

 ,

h

 , e

h

 

‐ Intricate analysis ‐ Moderate s/b ratio starting from approximately few percent to approximately 30%.

SLIDE 41

VH production with H  bb

Also a VBF analysis (CMS)

‐ Intricate analysis ‐ Moderate s/b ratio starting from approximately few percent to approximately 30%.

SLIDE 42

Main decays channels inputs

Channel categories ATLAS CMS ( at 125.4 GeV) Z exp Z obs M (GeV)  Z exp Z obs M (GeV)  1.2±0.3 4.6 5.2

126.0±0.5

1.1±0.2 5.2 5.7

124.7±0.3

ZZ (llll) 1.4±0.4 6.2 8.1

124.3±0.5

1.0±0.3 6.2 6.2

125.6±0.5

WW (lnln) 1.1±0.2 5.8 6.1

0.8±0.2

5.3 3.9



1.4±0.4 3.5 4.5

0.9±0.3

3.7 3.2 125 +9

7

W,Z H (bb*) 0.5±0.4 2.6 1.4

0.9±0.5

2.1 2.1

Combination
125.4±0.4

1.00±0.1 3

125.1±0.3

)  Signal strength (

0.5 1 1.5 2

ATLAS Preliminary

1

Ldt = 4.5-4.7 fb



= 7 TeV s

1

Ldt = 20.3 fb



= 8 TeV s = 125.36 GeV H m arXiv:1408.7084 0.27

0.27

+

= 1.17     H

arXiv:1408.5191 0.33

0.40

+

= 1.44  4l  ZZ*  H

0.20

0.22

+

= 1.08   l  l  WW*  H

ATLAS-CONF-2014-060 arXiv:1409.6212 0.4

0.4

+

= 0.5  b b  W,Z H

0.4

0.4

+

= 1.4     H

ATLAS-CONF-2014-061

Total uncertainty 

n

 1 

SM

 /  Best fit

0.5 1 1.5 2

0.29  = 1.00 

ZZ tagged  H

0.21  = 0.83 

WW tagged  H

0.24  = 1.13 

tagged    H

0.27  = 0.91 

tagged    H

0.49  = 0.93 

bb tagged  H

0.13  = 1.00 

Combined

CMS

Preliminary

(7 TeV)

1

(8 TeV) + 5.1 fb

1

19.7 fb

= 125 GeV

H

m

SLIDE 43

Mass [GeV]

Our Combination ATLAS Combined llll 

(*)

ZZ  ATLAS H    ATLAS H CMS Combined llll 

(*)

ZZ  CMS H    CMS H

0.2  A1 125.0 0.4  A2 125.4 0.5  A3 124.3 0.5  A4 126.0 0.3  C1 125.1 0.5  C2 125.6 0.3  C3 124.7 123 124 125 126 127 128

Currently Measured at ~0.16%

(still some gain from Stat, Syst more difficult!)

Precision through Combinations

SLIDE 44

Signal strength

1

1 2 3 4 5 6 7 8

ATLAS = 7 TeV s ,

1

Ldt = 4.5 fb



= 8 TeV s ,

1

Ldt = 20.3 fb



= 125.4 GeV

H

m ,    H

Total Stat. Syst. 

ggF



VBF



WH



ZH



H t t



SM

 /  Best fit

4
2

2 4 6 ZZ (2 jets)  H ZZ (0/1 jet)  H (ttH tag)    H (VH tag)    H (VBF tag)    H (0/1 jet)    H WW (ttH tag)  H WW (VH tag)  H WW (VBF tag)  H WW (0/1 jet)  H (ttH tag)    H (VH tag)    H (VBF tag)    H (untagged)    H bb (ttH tag)  H bb (VH tag)  H

0.13  = 1.00 

Combined

CMS

Preliminary

(7 TeV)

1

(8 TeV) + 5.1 fb

1

19.7 fb

= 125 GeV

H

m

Digression on Information Format

μ=1 Sub-channel signal strengths Production mode signal strengths (per channel) μ=1 =0 =0

ns

c 

i S

M i  Aic ic i{ggF,VBF,VH,ttH }



         f Br f  Lc

SLIDE 45

The Natural Width of the Higgs Boson

Is small therefore small couplings to the Higgs can be easily visible: tool for discovery! At LHC only cross section x branching ratio, no direct access to the Higgs total cross section (unlike e+e‐ collider from recoil mass spectrum) ‐ Direct measurement (on‐shell) with the ZZ(4l) and  channels [obs. (exp.)]: 4l < 2.6 (3.5) GeV [exp. 6.5 for =1] and  <5.0 (6.2) GeV ‐ Only measure ratio of couplings or coupling modifiers with specific assumptions ‐ Coupling properties measurements ‐ Constraints from invisible (and exotic decays) Total width: Interference in diphoton (SM shift of approximately 30 MeV) Use pT dependence of shift (~200 MeV limit expected for 3 ab‐1) Total width: Through off shell couplings

S

M  4.2 MeV

ATL‐PHYS‐PUB‐2013‐014

45

SLIDE 46

First step towards an global EFT analysis:

Interpreting our Data

ns

c  

i S

M i  Aic ic i{processes}



         f Br f  Lc

From the number of signal events fitted in analysis categories

46

SLIDE 47

‐ Link to an effective Lagrangian and use scale factors

First step towards an global EFT analysis:

Interpreting our Data

ns

c  

i S

M i  Aic ic i{processes}



         f Br f  Lc

From the number of signal events fitted in analysis categories

47

SLIDE 48

‐ Link to an effective Lagrangian and use scale factors

First step towards an global EFT analysis:

Interpreting our Data

For example, the main contribution (ggF) to the gg channel can be written as (under the assumption that couplings to SM particles are SM): ‐ Assuming narrow width approximation ‐ Assume the same tensor structure of the SM Higgs boson : JCP = 0++

ns

c  

i S

M i  Aic ic i{processes}



         f Br f  Lc

From the number of signal events fitted in analysis categories

i  g

2

 f  

2

 H

2

 H

2  0.085g 2  0.0023 2  0.91 48

SLIDE 49

Main results I : Probing the coupling to SM particles

Checking the direct and indirect couplings to fermions
Probing specific composite models

V



0.5 1 1.5

f



2
1

1 2

95% C.L.

b b  H    H Z Z  H WW  H    H

Preliminary

CMS

(7 TeV)

1

(8 TeV) + 5.1 fb

1

19.7 fb

Observed SM Higgs

V

 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 1.6

F



2
1

1 2 3 4

bb  H bb  H    H    H 4l  H 4l  H  l  l  H  l  l  H    H    H

bb  H    H 4l  H  l  l  H    H Combined SM Best Fit

1

Ldt = 20.3 fb



= 8 TeV s

1

Ldt = 4.6-4.8 fb



= 7 TeV s

ATLAS Preliminary

SLIDE 50

Main results II : Probing the W to Z ratio (custodial symmetry)

SLIDE 51

Main results III : Probing physics beyond the Standard Model

(In the decays and/or in the loops)

Also direct invisible

nly search

SLIDE 52

There are important signs not to be missed!

mass (GeV)

1 2 3 45 10 20 100 200

1/2

r (g/2v)



2

10

1

10 1 W Z t b 

) fit  (M, 68% CL 95% CL 68% CL 95% CL SM Higgs 68% CL 95% CL SM Higgs

CMS

Preliminary

(7 TeV)

1

(8 TeV) + 5.1 fb

1

19.7 fb

SLIDE 53

Test of SUSY (and 2 HDMs)

mass (GeV)

1 2 3 45 10 20 100 200

1/2

r (g/2v)



2

10

1

10 1 W Z t b 

) fit  (M, 68% CL 95% CL 68% CL 95% CL SM Higgs 68% CL 95% CL SM Higgs

CMS

Preliminary

(7 TeV)

1

(8 TeV) + 5.1 fb

1

19.7 fb

SUSY

SLIDE 54

Test of SUSY (and 2 HDMs)

SLIDE 55

mass (GeV)

1 2 3 45 10 20 100 200

1/2

r (g/2v)



2

10

1

10 1 W Z t b 

) fit  (M, 68% CL 95% CL 68% CL 95% CL SM Higgs 68% CL 95% CL SM Higgs

CMS

Preliminary

(7 TeV)

1

(8 TeV) + 5.1 fb

1

19.7 fb

Test of Compositness

SLIDE 56

Cornering the Top Yukawa Coupling

SLIDE 57

Cornering (directly) the top Yukawa coupling

Analysis strategy

2 channels t(lvb)t(qqb)H(bb) and t(lvb)t(lvb)H(bb)
Challenging tt+jets background…
tt+jets and tt+HF tamed

ttH(bb)

ATLAS‐CONF‐2014‐011

SLIDE 58

Cornering (directly) the top Yukawa coupling

Analysis strategy

2 channels t(lvb)t(qqb)H(bb) and t(lvb)t(lvb)H(bb)
Challenging tt+jets background…
tt+jets and tt+HF tamed

Irreducible not critical

13%

ttH(bb)

58

Light rejection crucial

ATLAS‐CONF‐2014‐011

SLIDE 59

Preliminary Simulation ATLAS

1

L dt = 20.3 fb



= 8 TeV, s = 125 GeV

H

m Single lepton

B S / 0.0 0.5 1.0 4 j, 2 b S/B < 0.1% B S / 0.0 0.5 1.0 4 j, 3 b S/B = 0.2% B S / 0.0 0.5 1.0 4 b  4 j, S/B = 1.3% B S / 0.0 0.5 1.0 5 j, 2 b S/B = 0.1% B S / 0.0 0.5 1.0 5 j, 3 b S/B = 0.4% B S / 0.0 0.5 1.0 4 b  5 j, S/B = 2.3% B S / 0.0 0.5 1.0 6 j, 2 b  S/B = 0.2% B S / 0.0 0.5 1.0 6 j, 3 b  S/B = 0.9% B S / 0.0 0.5 1.0 4 b  6 j,  S/B = 3.8%

Cornering (directly) the top Yukawa coupling

Analysis strategy

2 channels t(lvb)t(qqb)H(bb) and t(lvb)t(lvb)H(bb)
Challenging tt+jets background…
tt+jets and tt+HF tamed
Also used kinematic discrimination to further

constrain backgrounds and discriminate signal

Results:

ttH(bb)

59 ATLAS‐CONF‐2014‐011

SLIDE 60

3.3W

2  5.1tW 2.8t 2

Cornering the top Yukawa coupling

t(t)H()

Leptonic channel Hadronic channel Inclusive  limit from process assuming W = 1 Analysis reinterpretation

ATLAS‐CONF‐2014‐043

tH contribution at negative t 95% CL exclusion ],1.3][8.1,[

(],1.2][7.9,[)

SLIDE 61

Measurements of Differential Cross Sections

SLIDE 62

Differential Cross sections (II)

Evidence for Spin 0 Nature

62

*)| [fb]  / d|cos(

fid

 d 20 40 60 80 100 120 140

Preliminary ATLAS data

syst. unc.

H X ) + ES HR ( H  gg = 1.15) ggF K ( H t t + VH = VBF + H X

= 8 TeV s ,    H



1

dt = 20.3 fb L

*)|  |cos( 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 data / prediction 2 4 6

More to learn from differential distributions which are sensitive to the main quantum numbers Spin and CP in many channels

H 

PLB 726 (2013)

To be submitted soon and ATLAS‐CONF‐2013‐072 PLB 726 (2013)

SLIDE 63

Differential Cross Sections

(Differential and fiducial cross sections in dijet ‐ Diphoton channel)

Experimental as well as TH endeavor !

SLIDE 64

Differential Cross sections

‐ Our results rely on the Higgs transverse momentum or jet multiplicities ‐ Sensitive to new physics in the content of the production loop

64

[fb/GeV]

T

p / d

fid

 d

2

10

1

10 1

Preliminary ATLAS data

syst. unc.

H X ) + ES HR ( H  gg = 1.15) ggF K ( H t t + VH = VBF + H X = 8 TeV s ,    H



1

dt = 20.3 fb L

[GeV]

  T

p 20 40 60 80 100 120 140 160 180 200 data / prediction 2 4 [fb]

fid

 5 10 15 20 25 30 35

Preliminary ATLAS data

syst. unc.

H X ) + MiNLO HJ+PS ( H  gg = 1.54) ggF K ( H t t + VH = VBF + H X = 8 TeV s ,    H



1

dt = 20.3 fb L > 30 GeV jet T p jets

N 1 2 3  data / prediction 2 4

H 

H  4l

ATLAS‐CONF‐2014‐044 To be submitted soon and ATLAS‐CONF‐2013‐072

SLIDE 65

Differential Cross sections

‐ Large number of observable tested ‐ Higgs started to provide Rivet routines! ‐ Entering also HEP data

65

Ratio of 1st moment relative to data

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8

|

jj

  | *)|  |cos( |

jj

 

  | |

jj

y  |

T

H

j2 T

p |

j1

y |

j1 T

p

50 GeV jets

N

jets

N |

 

y |

  T

p

Preliminary ATLAS

= 8 TeV s ,    H



1

dt = 20.3 fb L

H t t + VH = VBF + H X

H X +

OWHEG

P

H X MiNLO HJ + H X MiNLO HJJ +

H X +

ES

HR data

syst. unc.

Ratio of 2nd moment relative to data

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8

|

jj

  | *)|  |cos( |

jj

 

  | |

jj

y  |

T

H

j2 T

p |

j1

y |

j1 T

p

50 GeV jets

N

jets

N |

 

y |

  T

p

Preliminary ATLAS

= 8 TeV s ,    H



1

dt = 20.3 fb L

H t t + VH = VBF + H X

H X +

OWHEG

P

H X MiNLO HJ + H X MiNLO HJJ +

H X +

ES

HR data

syst. unc.

H 

To be submitted soon and ATLAS‐CONF‐2013‐072

SLIDE 66

Exploring the far Off Shell mass region and the Off Shell couplings

SLIDE 67

Off Shell Couplings

Far Off Shell domain

ZZ tt

Agnostic to k‐factor!

R=1 (Verified in the soft colinear approximation) (G. Passarino)

95% CL limit obs. (exp.) OffShell < 6.7 (7.9)

ATLAS‐CONF‐2014‐042

Extremely interesting analysis: ‐ The constraint on the total width is of limited interest ‐ Investigate more the EFT approach (See Christophe’s talk)

SLIDE 68

Inspiring … For self couplings

Determination of the scalar potential, essential missing ingredient : self

couplings 3 ~ mH

2/(2v) , 4 ~ mH 2/(8v2)!

Very similar analysis as the off shell couplings!

4 : hopeless in any planed experiment (?) 3 : very very hard in particular due to the double H production, which also interferes with the signal… … some hope? pp  HH  bb

r bb+- (under study)

Extremely challenging!

SLIDE 69

1.‐ Improve/consolidate the current channels 2.‐ Synergy with Theory

‐ Signal ‐ Need an improved PDF prescription ‐ N3LO ‐ Backgrounds ‐ Top transverse momentum and jet mult. ‐ V+jets ‐ NNLO diboson

3.‐ Exploration of the power of EFT has started

‐ Yield a more precise and robust framework for the couplings analysis ‐ Yield a framework to define the sensitive observables (see Christophe’s talk) ‐ Yield a very general framework for indirect tests of new physics through the

verall consistency of all EW and Higgs measurements

Towards Precision Higgs Physics

SLIDE 70

Higgs and Dark Matter

‐ Light DM in the total width of the Higgs boson? ‐ Heavier DM production of DM at LHC through direct searches of (increased interest): ‐ Mono jet ‐ Mono photon ‐ Mono W or Z ‐ Mono Higgs!

Covered in a seminar by

I. Vivarelli November 11, 2014
L. Feng et al., PLB 728 (2014)

SLIDE 71

Invisible Higgs Channels I

Indirect constraints on the invisible and undetected Branching

(a fortiori on the invisible branching)

Re-interpretation of mono-jet and mono-W or Z analyses

For a 125 GeV Higgs: Brinv/SM < 1.6 at 95%CL (obs)

H0

g,, Brinv,undet

SLIDE 72

Invisible Higgs Channels I

Search for a dilepton pair compatible with a Z

and missing transverse energy

Analyses using fits to MET (ATLAS) or MT (CMS)

[GeV]

T

m 200 400 600 800 entries / 50 GeV 20 40 60

CMS preliminary data =125 H m DY+jets WZ ZZ VVV WW/top/W+jets

1

L = 24.4 fb = 7+8 TeV s

[GeV]

H

M

105 110 115 120 125 130 135 140 145 Z H , S M

 /

in v  H

B R 

Z H

 9 5 % C L l i m i t o n

0.5 1 1.5 2 2.5 3 Observed Expected  1  Expected  2  Expected ll+MET  ZH

1

L=5.1 fb  =7 TeV, s

1

L=19.6 fb  =8 TeV, s CMS Preliminary

For a 125 GeV Higgs:

ATLAS

Brinv < 65% at 95%CL (obs) Brinv < 84% at 95%CL (exp)

CMS

Brinv < 75% at 95%CL (obs) Brinv < 91% at 95%CL (exp)

SLIDE 73

Invisible Higgs Channels II

Associated production with a Z in bb (CMS only)
Search following closely VH(bb)
Contribution from VH(bb) has very little impact

For a 125 GeV Higgs:

Brinv/SM < 1.8 at 95%CL (obs) Brinv/SM < 2.0 at 95%CL (exp)

[GeV]

H

m 110 120 130 140 150

ZH,SM

 /

inv

x BR

ZH

 95% CL limit on

1 2 3 4 5 6 7

Observed Expected  1  Expected  2  Expected

1

= 8 TeV, L = 18.9 fb s CMS Preliminary

inv)  ) H( b b  Z(

CMS-PAS-HIG-13-028

SLIDE 74

Invisible Higgs Channels IV

Search in the VBF production mode
Main selection on Mjj, jj, and large MET

For a 125 GeV Higgs:

CMS

Brinv < 69% at 95%CL (obs) Brinv < 53% at 95%CL (exp)

Events / 100 GeV

3

10

2

10

1

10 1 10

2

10

3

10

4

10

CMS Preliminary

1

= 8 TeV L = 19.6 fb s

Observed Signal 100%BR V+jets tt+DY+VV

[GeV]

jj

M

500 1000 1500 2000 2500 3000 3500 MC Data - MC

1

1

(GeV)

H

m

115 120 125 130 135 140 145 i n v

9 5 % C L l i m i t o n B F

0.2 0.4 0.6 0.8 1 1.2 1.4

CMS Preliminary Combination of VBF and invisible  ZH, H

=8 TeV L = 19.6/fb (VBF + ZH) s =7 TeV L = 5.1/fb (ZH) s

Observed Expected (68%) Expected (95%)

CMS-PAS-HIG-13-013

SLIDE 75

Higgs Portal Interpretation

‐ Visible – Invisible combination ‐ Corresponding limit :

Brinv < 37% (39) % at 95%CL

Pure Higgs portal interpretation

SM DM

SLIDE 76

Searches for Additional Higgs bosons

Extremely important to search for additional states of the EW breaking sector e.g. SUSY requires at least two doublets of complex scalar fields (therefore additional scalar states are expected)

SLIDE 77

Search for a narrow resonance decaying to a pair of photons

Fiducial cross section limits

ATLAS‐CONF‐2014‐031

Nano Review of BSM Channels

Charged Higgs
Main current analysis H± to 
H± to cs
High mass specific H± to AW
High mass specific H± to tb
Additional CP Odd/Even
Nice results on 
Also searched for in 
Also searched for in bb(b)
Needs searches in the tt channel
New results on hh, soon coming hZ

  extending mass domain

ZZ in 4l, llqq, llvv, vvqq
WW in lvlv and lvqq
NMSSM (mainly low mass)
Direct low mass 
Exotic cascades h to aa to four photons, or four taus, , etc…

H 

SLIDE 78

Nano Review of BSM Channels

Specific model dependent searches

Search for two states in the spectrum in this case h and H together!

Becoming a standard! (see Roger’s talk)

… and much more !

Doubly charged Higgs
Cascade decays
Higgs decays to dark Z, hidden valley pions
Model independent searches for H(gg) + X

SLIDE 79

Nano Review of BSM Channels

Specific model dependent searches

Search for two states in the spectrum in this case h and H together!

Becoming a standard! (see Roger’s talk)

… and much more !

Doubly charged Higgs
Cascade decays
Higgs decays to dark Z, hidden valley pions
Model independent searches for H(gg) + X

… and more !

NMSSM As and Hs w/ 6’s, etc…

(Thanks Margarete)

Specific Higgs SUSY decays

(Thanks Georg)

SLIDE 80

Run 2 A new era of exploration

and precision…

… No « No Loose Theorem » anymore…

SLIDE 81

ATLAS Upgrades

Phase 0 Upgrade

‐ Additionnal insertable b‐layer (Pixels) ‐ New beam pipe ‐ Complete muon coverage ‐ Repairs (TRT, LAr, Tile)

Phase 1 Upgrade

‐ New Small Wheel (Forward muons) for L1 muon trigger ‐ Topological L1 trigger processors ‐ High granularity L1 Calorimeter trigger

Phase 2 Upgrade

‐ Completely new tracker (large eta?) ‐ Calorimeter eletronics upgrade ‐ Possible L1 track trigger ‐ Possible change to the forward calorimeters

CMS Upgrades

Phase 0 Upgrade

‐ Complete muon coverage ‐ Replace HCAL photodetectors (forward and outer)

Phase 1 Upgrade

‐ New pixel detector ‐ New beam pipe ‐ L1 trigger upgrade ‐ HCAL electronics

IBL light rejection twice better than current ATLAS

SLIDE 82

How to get to Run‐2?

SLIDE 83

How do we get to Run‐2?

SMACC (Superconducting Magnets and Circuits Consolidation)

SLIDE 84

Event taken at random (filled) bunch crossings

A New Machine at a New Energy Forntier

Parameter 2010 2011 2012 Run 2 C.O.M Energy 7 TeV 7 TeV 8 TeV 13 TeV Bunch spacing / k 150 ns / 368 50 ns / 1380 50 ns /1380 25 ns /2508  (mm rad) 2.4-4 1.9-2.3 2.5 1.9 * (m) 3.5 1.5-1 0.6 < 0.6 L (cm-2s-1) 2x1032 3.3x1033 ~7x1033 1.6 1034

… in LS1

SLIDE 85

What can we expect?

Elaborate a concrete analysis program based on

the following scenarios

– Spring‐Summer 2015 0‐1 fb‐1 at 50 ns – EPS 2015 < 1 fb‐1 at 50ns – LHCP ‐ LP 2015 1 fb‐1 at 50ns – Full 2015 10‐ fb‐1 at 25ns – Full Run II 75‐100 fb‐1 at 25ns

Moriond 2016

Important milestone for the entire physics program

SLIDE 86

The rough Picture…

1 10 100 1000 10000

QBH (6 TeV) QBH (5 TeV) Q* (4 Tev) Z' SSM (3 TeV) gluino pair (1.5 TeV) stop pair (0.7 TeV) A(0.5 TeV, ggF+bbA) ttH ttZ tt WH H (VBF) H (ggF) t (t-channel) t (s-channel) ZZ Z(ll) W(ln) Minimum bias

9000 370 56 10 46 8.4 4.0 3.9 3.6 3.3 2.9 2.4 2.3 2.5 2.2 2.0 1.7 1.6 1.2

SLIDE 87

The critical b‐Yukawa

‐ Projections: Validating the parametrization with data! ‐ Estimate the sensitivity vi the llbb (eventually most sensitve) and lvbb ‐ Of course includes the increase top background estimates 300 fb‐1 O(60) PU events: 4

This is without the very sensitive vvbb channel! Run 2 could be saying a strong word on this channel possibly have an observation at more than 3)

~60% of the width

SLIDE 88

The Crucial ttH Channels

= 125.6 GeV

H

at m

SM

 /  Best fit

10
8
6
4
2

2 4 6 8 10

Combination Same-Sign 2l 3l 4l

h



h

 b b  

CMS

1

= 8 TeV, 19.3-19.7 fb s ;

1

= 7 TeV, 5.0-5.1 fb s

‐ Long term analyses: ‐ ttH () ‐ ttH () ‐ Current channels:

‐ ttH (bb) 1 and 2‐leptons ‐ ttH (gg) semi and fully hadronic ‐ ttH (WW and tt) multileptons and taus

‐ Not trivial to project without systematics! ‐ Diphoton  O(200%) stat. Dominated ‐ Multileptons  O(100%) syst. Important

Not trivial to improve

‐ bb channel  O(150%) syst. Critical

Even harder

‐ Combination Hopefully an observation at Run‐2 (3)! ‐ Combination ATLAS‐CMS crucial but also extremely intricate!

SLIDE 89

Conclusions

‐ Run‐1 has been an amazing success ! ‐ The discovery of the Higgs boson is a success of the experimental and TH community ‐ Run‐2 is an imminent new machine ‐ Close to double centre‐of‐mass energy ‐ Should deliver approximately four times the Run‐1 Luminosity ‐ Exciting opportunities for discoveries (leave no stone unturned) ‐ Continue our vast precision program ‐ Now is the perfect time to start a PhD at LHC!

SLIDE 90

The ATLAS detector The CMS detector

SLIDE 91

Preamble I: The ATLAS and CMS Detectors In a Nutshell

Sub System ATLAS CMS Design Magnet(s)

Solenoid (within EM Calo) 2T 3 Air‐core Toroids Solenoid 3.8T Calorimeters Inside

Inner Tracking

Pixels, Si‐strips, TRT PID w/ TRT and dE/dx Pixels and Si‐strips PID w/ dE/dx

EM Calorimeter

Lead‐Larg Sampling w/ longitudinal segmentation Lead‐Tungstate Crys. Homogeneous w/o longitudinal segmentation

Hadronic Calorimeter

Fe‐Scint. & Cu‐Larg (fwd) Brass‐scint. & Tail Catcher

Muon Spectrometer System

Acc. ATLAS 2.7 & CMS 2.4

Instrumented Air Core (std. alone) Instrumented Iron return yoke

4 11