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Theory evaluation of LHC data for Physics beyond the Standard Model
Riccardo Rattazzi
After the Higgs and Nothing Else
Riccardo Rattazzi
Effective Quantum Field Theory ideology
✦ gauge symmetry
✦ field content
✦ local effective lagrangian
✴ renormalizability
✴ global symmetries
needn’t be fundamentalbut just accidental low energy features
The Standard Model as effective field theory
Λ2UV � 1TeVwith fundamental scale
LSM = d=4Lkin + gAµFγµF + YijFiHFj + λ(H†H)2
+bij
ΛUV
LiLjHH
+cijkl
Λ2UV
FiFjFkF� +cij
ΛUV
FiσµνFjGµν + . . . d>4
+ . . .
LSM = d=4Lkin + gAµFγµF + YijFiHFj + λ(H†H)2
+bij
ΛUV
LiLjHH
+cijkl
Λ2UV
FiFjFkF� +cij
ΛUV
FiσµνFjGµν + . . . d>4
+ . . .
LSM = d=4Lkin + gAµFγµF + YijFiHFj + λ(H†H)2
( pointlike limit ) nicely accounts for ‘what we see’ ΛUV � TeV
+bij
ΛUV
LiLjHH
+cijkl
Λ2UV
FiFjFkF� +cij
ΛUV
FiσµνFjGµν + . . . d>4
+ . . .
LSM = d=4Lkin + gAµFγµF + YijFiHFj + λ(H†H)2
( pointlike limit ) nicely accounts for ‘what we see’ ΛUV � TeV
d=4+ θ GµνGµν
+ cΛ2UV H
†H d=2
+bij
ΛUV
LiLjHH
+cijkl
Λ2UV
FiFjFkF� +cij
ΛUV
FiσµνFjGµν + . . . d>4
+ . . .
LSM = d=4Lkin + gAµFγµF + YijFiHFj + λ(H†H)2
( pointlike limit ) nicely accounts for ‘what we see’ ΛUV � TeV
d=4+ θ GµνGµν
d=0+Λ4UV
√g
the three
problems
+ cΛ2UV H
†H d=2
+bij
ΛUV
LiLjHH
+cijkl
Λ2UV
FiFjFkF� +cij
ΛUV
FiσµνFjGµν + . . . d>4
+ . . .
LSM = d=4Lkin + gAµFγµF + YijFiHFj + λ(H†H)2
( pointlike limit ) nicely accounts for ‘what we see’ ΛUV � TeV
d=4+ θ GµνGµν
yij HFiFj
1
Λ2UV
FiFjFkF� + . . .
Λ2UV H
†H
Standard Model up to some
Hierarchy see-saw
Λ2UV � 1TeV
☺☺☹
yij HFiFj
1
Λ2UV
FiFjFkF� + . . .
Λ2UV H
†H
☺☺☹
Standard Model up to some
Hierarchy see-saw
Λ2UV � 1TeV
yij HFiFj
1
Λ2UV
FiFjFkF� + . . .
Λ2UV H
†H
☺☺☹
m2H
= �Λ2UV � Λ2
UV
Tuning!
Standard Model up to some
Hierarchy see-saw
Λ2UV � 1TeV
yij HFiFj1
Λ2UV
FiFjFkF� + . . .Λ2UV H
†H
☺ ☺ ☹
Natural SM : Λ2UV
<∼ 1TeV
The two possible microphysics scenarios
• B, L and Flavor: beautifully in accord with observation
• Hierarchy remains a mystery, probably hinting that the question was not correctly posed
• anthropic principle• failure of effective field theory ideology (UV/IR connection)
I. The SM is the correct description up to
II. The SM is not the correct description already at
• In the correct theory the hierarchy problem does not even arise (naturalness)• What about B, L and Flavor? In all models not nearly as nice as in SM
ΛUV � TeV
ΛUV ∼ 1TeV
��HH
Λmν ∼ v2
ΛΛ ∼ 1014 GeV
A high scale scenarioLd=4• experimental success (some 2- 3-σ glitches here and there)
• Θ-QCD and Dark Matter ➔ high scale axion
• gauge couplings ready to unify around
fa ∼ 1012 GeV
1015 <∼ M <∼ MPlanck
• neutrino masses
• RG-evolution of SM couplings, including remarkably do not require lower scales
λh
1
αi
lnµ
107 108 109
1010
1011
101210131014
1016
120 122 124 126 128 130 132168
170
172
174
176
178
180
Higgs pole mass Mh in GeV
ToppolemassM
tinGeV
1018
1019
1,2,3 Σ
Instability
Stability
Meta�stability
the fact that the SM lives dangerously perhaps points toan anthropic selection of parameters
though it is hard to tell
living dangerously
Elias-Miro, Espinosa,Giudice, Isidori, Riotto, Strumia ’11
Elias-Miro, Espinosa,Giudice, Isidori, Riotto, Strumia ’11
but watch your eyes
Elias-Miro, Espinosa,Giudice, Isidori, Riotto, Strumia ’11
Strumia’s courtesy
102 104 106 108 1010 1012 1014 1016 1018 1020
�0.04
�0.02
0.00
0.02
0.04
0.06
0.08
0.10
RGE scale Μ in GeVH
iggs
quar
ticco
uplin
g��
3Σ bands inMt � 173.4 � 0.7 GeV �gray�Αs�MZ� � 0.1184 � 0.0007�red�Mh � 125.7 � 0.3 GeV �blue�
Mt � 171.4 GeV
Αs�MZ� � 0.1163
Αs�MZ� � 0.1205
Mt � 175.3 GeV
102 104 106 108 1010 1012 1014 1016 1018 1020�0.020
�0.015
�0.010
�0.005
0.000
RGE scale Μ in GeV
Bet
afu
nctio
nof
the
quar
ticΒ Λ
3Σ bands inMt � 173.4 � 0.7 GeV �gray�Αs�MZ� � 0.1184 � 0.0007�red�Mh � 125.7 � 0.3 GeV �blue�
102 104 106 108 1010 1012 1014 1016 1018 1020�0.2
�0.1
0.0
0.1
0.2
RGE scale Μ in GeV
Λ�y t2
3Σ bands inMt � 173.4 � 0.7 GeV �gray�Αs�MZ� � 0.1184 � 0.0007�red�Mh � 125.7 � 0.3 GeV �blue�
102 104 106 108 1010 1012 1014 1016 1018 1020�0.4
�0.2
0.0
0.2
0.4
0.6
0.8
RGE scale Μ in GeV
Β Λ�Β Λ�to
pco
ntrib
utio
n�
3Σ bands inMt � 173.4 � 0.7 GeV �gray�Αs�MZ� � 0.1184 � 0.0007�red�Mh � 125.5 � 0.3 GeV �blue�
Figure 1: Upper: RG evolution of λ and of βλ varying Mt, αs, Mh by ±3σ. Lower: Sameresults factoring out the overall reduction in the couplings, dividing by appropriate powers ofthe top Yukawa coupling, chosen as representative. In the bottom-right plot we divided βλ bythe one-loop top contribution to it, 3y4
t.
15
The two natural scenarios for electroweak symmetry breaking
Elementary Higgs exists but a symmetry
protects its mass
No elementary Higgs exists
Supersymmetric Models
Technicolor,Composite Light Higgs
(and its holograms)
Large Extra Dimensions: exciting, fantastic, great, but not very plausible without extra mass scale separation
Plus a list of not even wrong scenarios...
Flavor ?
Ld≤4 = m2ijQ
†i Qj +AijY
Dij QiDjHd + λijkUiDjDk + . . .
Supersymmetry: the existence of scalar matter fields introduces a myriad of d ≤ 4 terms violating F, B and L
Naive Composite Higgs (TC) : the Yukawa themselves are d > 4
Yij H QiLQ
jR → Yij
1
Λ2F
(ΨΨ)QiLQ
jR
mij = Yijv3FΛ2F
ΛF must be not too far above weak scale: expect unwanted FCNC
In all natural models, extra assumptions (often clever) are needed to meetflavor physics constraints
Symmetrypick a subgroup ofpick a set of spurions to break itconstruct a lagrangian using the selection rules
U(3)Q × U(3)U × U(3)D × U(3)L × U(3)E
Dynamicsmass mixing hierarchy from radiative correctionsflavor from geography in extra-dim flavor from partial compositeness holography
Approaches
In all natural models, extra assumptions (often clever) are needed to meetflavor physics constraints
Symmetrypick a subgroup ofpick a set of spurions to break itconstruct a lagrangian using the selection rules
U(3)Q × U(3)U × U(3)D × U(3)L × U(3)E
Dynamicsmass mixing hierarchy from radiative correctionsflavor from geography in extra-dim flavor from partial compositeness holography
Approaches
unfortunately disfavored
in natural theories
What naturalness demands
➤
➤
topδm2H
=
supersoft models: Higgs mass parameter fully saturated by IR physics
•dirac gauginos in supersymmetry•general composite Higgs
mh = 125GeV
tuning
soft models: Higgs mass logarithmically sensitive to UV
•MSSM and its extensions with high scale mediation
�400GeV
M
�2
∼ 3λ2t
8π2M2
m2h ∼ m2
Z ∼ m2t
mh = 125GeV
�125GeV
m
�2
tuning
SM + Higgs
Mass
SM Newδm2H
= + ∼ 0
The more natural the theory the more the Higgs rates deviate from SM
+
+ +
SM + Higgs
new states
Mass
SM Newδm2H
= + ∼ 0
The more natural the theory the more the Higgs rates deviate from SM
+
+ +
Little Higgswith T-parity
⋂minimal
O(1)
O(αt/4π)
Supersymmetry
•higgs couplings•EWPT • • ...
(�1, �2, �3)
b → sγ
super-soft
⋂δO
OSM∼ m2
weak
m2
softO(1)
O(αt/4π)
Compositeness δO
OSM∼ v2
f2
•EWPT • • direct searches (susy)
(�1, �2, �3)
b → sγ
δO
OSM< 1 (10%)imply
in most cases, O(1) deviations in Higgs rates were already disfavored
Perspective on Supersymmetrybefore and after LHC 7/8
t
g
χ+ χ0
Z
once upon a time, expectation in the less clever models was
�
LEP/Tevatronml, mχ+ >∼ 100GeV
mq, mg >∼ 300GeV
t
g
χ+
χ0
Z
mh > 114.4GeV MSSM
1TeV
Z
t
g
χ0
Giudice, Rattazzi ‘06
LEP/Tevatronml, mχ+ >∼ 100GeV
mq, mg >∼ 300GeV
t
g
χ+
χ0
Z
mh > 114.4GeV MSSM
1TeV
NMSSM
t
Z
Z
t
g, q, �
1TeV
Before LHC: natural and simple spectrum possible within NMSSM
• situation only slightly worse with • GUT perturbativity borderline, but needn’t worry too much
see Barbieri et al 2013
mh � 125GeV Hall, Pinner, Ruderman ’11
• direct searches have however eliminated the natural region of the most straighforward NMSSM scenario (in particular flavor universal sfermion
masses)
After LHC
Z
1TeV
tg, q, �χ0
• situation only slightly worse with • GUT perturbativity borderline, but needn’t worry too much
see Barbieri et al 2013
mh � 125GeV Hall, Pinner, Ruderman ’11
• direct searches have however eliminated the natural region of the most straighforward NMSSM scenario (in particular flavor universal sfermion
masses)
After LHC
Z
1TeVtg, q, �
χ0
simplest scenarios were under pressure already before LHC
What about more ‘structured’ models, those that stick tonaturalness like a mussel to her reef?
MSSM:
NMSSM: simplest scenarios came under pressure with LHC
Natural SUSYnot-so-un-
TeV
mt<∼ 500GeV some other physics ( ex NMSSM) takes care of mh
consider all possible ways to suppress the signal:
Dirac gluino, RPV, compressed spectrum,...
Natural SUSYnot-so-un-
TeV
Dirac gluino
mt<∼ 500GeV some other physics ( ex NMSSM) takes care of mh
consider all possible ways to suppress the signal:
Dirac gluino, RPV, compressed spectrum,...
?
notice Br(4t) < 0.25 in relevant scenario: 15-20% reduction of bound Barbieri, Pappadopulo ‘09
1
1
0.1
0.25
0.5
2
5
400 600 800 1000 1200 14000
200
400
600
800
1000
Gluino mass � GeV �
LSPmass�Ge
V�
g0� g� 0 production, g0
���t t � 0
CMS 1� lep � n jets �6� 19.4 fb � 1Contours of Σ � Σ lim
Mahbubani ‘13
however the other channels (tttb, ttbb) add to same signalexpect compensation, in the end bound should not change much
what about some help from baryonic RPV?
some relaxation but not much
forget about majorana gluino and go to dirac: supersoft stop masseszoom on stops and higgsinos
impressive but significant natural regions with squashed spectra remain
probably these regions can already be more significantly constrained bydifferent analysis of present data
also addition of , , production should be considered bLtLtR
Kribs, Martin, Menon ‘13
Delgado, Giudice, Isidori, Pierini, Strumia ‘13
what about RPV decaying , , ? bLtLtR
b
s
t
g
h01,2 h
±
600GeV
t
mh +mt > mt
CMS 7 TeV data below 250 Gev
wait for upcoming 8 TeV
bs
c bs
u, c
t
g
b, d, s
ATLAS, 7 TeV 4.6 &-1
mg > 666GeV
what about topless gluino decays?
0.01pb0.03pb
0.1pb
0.32pb1pb
400 600 800 1000400
600
800
1000
1200
1400
mu�Rin GeV
mg�inGeV
pp�p��u�Ru�R,u�R�u�R��,...� � 8TeV LHC
CMS 5 fb�1�7 TeV
CDF 6.6 fb�1
but bound relaxed if binoenters decays chain
gg → 10jets
Pappadopulo ‘13
bs
c bs
u, c
t
g
b, d, s
ATLAS, 7 TeV 4.6 &-1
mg > 666GeV
what about topless gluino decays?
0.01pb0.03pb
0.1pb
0.32pb1pb
400 600 800 1000400
600
800
1000
1200
1400
mu�Rin GeV
mg�inGeV
pp�p��u�Ru�R,u�R�u�R��,...� � 8TeV LHC
CMS 5 fb�1�7 TeV
CDF 6.6 fb�1
but bound relaxed if binoenters decays chain
gg → 10jets
Pappadopulo ‘13
ATLAS & CMS are hunting down Supersymmetry in nooks and cranniesLooking forward to next run and to even more clever analyses
Too early tough to fully overthrow naturalness in favorof scenarios like, for instance, mini-split SUSY
but pressure is clearly building up
anyway, wait to hear Nima
Compositeness
Flavor: only option is partial compositeness
without any additional symmetrym∗ >∼ 10− 20TeV
m∗ >∼ 40TeV
m∗ >∼ 150TeV
FCNC
edms
µ → eγ
with combination of SU(2)’s and SU(3) can bring scale down to ∼TeV
H
f f
Redi ’12Babrbieri, Buttazzo, Sala, Straub, Tesi ’12
tL
T
V (H) =top
expectations from naturalness
partners(B−1/3, T2/3, X5/3, Ξ8/3, . . . )
V ≡ V (H/f)
v2
f2= O(1)
�400GeV
mT
�2
= O(1)
mh � 125GeVgeneric
Electroweak Precision Tests
W, Zh
∆�S, ∆ �T
pessimist
optimist
W, Z V∆�S ∼ m2
W
m2V
m2V
>∼ 2− 3TeV
EWPT already imply some tuning
technical naturalness demands structural complexity
v2
f2<∼ 0.05 (0.2)
(mV � mT )
from EWPT
Higgs couplings
δg
gSM
∼ v2
f2<∼ 0.2
wait for more integrated luminosity to break new grounds
λ = 3
λ = 0.3
ξ ≡ v2
f2= 0.2
c1
M5/3
this is a very significant direct ‘test’ of naturalnessbut result not fully unexpected in view of LEP/etc...
CMSlatest
De Simone, Matsedonkyi, Rattazzi , Wulzer ’12
λ = 3
λ = 0.3
ξ ≡ v2
f2= 0.2
c1
M5/3
this is a very significant direct ‘test’ of naturalnessbut result not fully unexpected in view of LEP/etc...
CMSlatest
De Simone, Matsedonkyi, Rattazzi , Wulzer ’12
λ = 3
λ = 0.3
ξ ≡ v2
f2= 0.2
c1
M5/3
this is a very significant direct ‘test’ of naturalnessbut result not fully unexpected in view of LEP/etc...
CMSlatest
De Simone, Matsedonkyi, Rattazzi , Wulzer ’12
?
Vector Resonances
q
qWL
WL
• resonances couple ‘superweakly’ to light fermions
• significantly different from weakly coupled W’ and Z’
• LHC bound still below 2 TeV for gV >3
• wait for LHC13 to break new ground
=g2WgV
� gW= gV
V V
σ ∼ 10 fb
�3
gV
�2 �2TeV
mV
�6
upcoming ‘theorists analysis’ : Contino, Grojean, Pappadopulo, Thamm, Torre, Wulzer
Higgzoology
SM + Higgsnew states
Mass
Can use effective lagrangian to describe deviations from SM
= simple parametrization encompassing a large class of models
SM + Higgs
new states
Mass
Can use effective lagrangian to describe deviations from SM
= simple parametrization encompassing a large class of models
ci × mi
vcV × 2m2V
v
cγcg
cV > 1 only if ∃ scalar of electric charge 2
cb > 1, ct < 1
cb < 1, ct > 1
cV , cf < 1 cg, cγ ∼ 0
MSSM
NMSSM dominated quartic
Composite Higgs
No clear trend of deviation from SMCompatible with SM within 30%
Higgs comin’ !!
Welcome Higgs !!
The precision frontier
singleHiggs
physicsmeasures fine tuning
HL-LHC ILC-LEPpone
5% 1%
precision Higgs physics breaks ground in the test of naturalnessthough it can only give us indirect clues
EWPT10%
semidirectclues at CLIC sensitive to tuning of ~1%
g2NPv2
M2NP
<∼
MNP
tuning
�0.4TeV
MNP
�2
5 10 15 20 25 30
10�4
0.001
0.01
0.1
�mh
MNP
�2
The energy frontier
LHC14 HE-LHC
Summary• discovery of Higgs boson with rates in agreement with SM within
the present precision of 30% is far from unexpected: it is basically a corollary of results of LEP/Tevatron/B-factories
• direct searches are directly pushing several scenarios (especially in SUSY) into 1% tuning grounds, though that is basically were the simplest (and maybe nicest) models were already expected by indirect reasoning (ex, MSSM with flavor universal soft terms)
• LHC searches are now also putting significant pressure on cleverly natural models, though regions with moderate tuning are not ruled out yet
• Refined analyses & LHC13 can break grounds on those regions and perform a comprehensive test of naturalness
•HL-LHC will break grounds in EW physics by testing Higgs rates at, so it seems, 5%