From the TeVatron to the LHC: What could lie beyond the SM?
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Transcript of From the TeVatron to the LHC: What could lie beyond the SM?
From the TeVatron to the From the TeVatron to the LHC: What could lie beyond LHC: What could lie beyond
the SM?the SM?Monica D’OnofrioIFAE-Barcelona
HEP Seminar, University of Oxford, 28th October
2008
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 2
The Standard ModelThe Standard Model Matter is made out of fermions:
3 generations of quarks and leptons Forces are carried by Bosons:
Electroweak: ,W,Z Strong: gluons
Remarkably successful description of known phenomena:
• predicted the existence of charm, bottom, top quarks, tau neutrino, W and Z bosons.• Very good fit to the experimental data so far
but ...
The missing piece: The missing piece: the Higgs the Higgs What is the origin of masses? Within SM, Higgs field gives mass
to Particles (EWK symmetry breaking) SM predicts existence of a new
massive neutral particleNot found yet!
Theory does not predict its mass LEP limit: mH>114 GeV @ 95% CL Indirect limit from EW data: - Preferred value: mH = 84+34
-26 GeV
- mH < 154 GeV @ 95% CL
with S (MZ) = 0.1185±0.0026, S(5)had=0.02758±0.00035
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 3
WOULD THE HIGGS DISCOVERY COMPLETE OUR UNDERSTANDING OF NATURE ?
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 4
Beyond SM: Beyond SM: the Unknown the Unknown
Many possible new particles and theories SuperSymmetry Extra Dimension New Gauge groups (Z’, W’) New fermions (e*, t’, b’ …) …
Can show up in direct searches or as subtle deviations in precision measurements
The Standard Model is theoretically incomplete
• Mass hierarchy problem
radiative correction in Higgs sector
• Unification
• Dark Matter
• Matter-antimatter asymmetry
mH2 ~ 2
= Mpl ?
Hf
Outline Outline Tevatron and the CDF and D0 experiments Tevatron sensitivities: achievements understanding the SM The SM Higgs Searching for physics beyond SM
Supersymmetry mSUGRA-inspired searches:
Squark/gluino Chargino/neutralinos
GMSB-inspired searches Diphoton+X Delayed photon analysis
MSSM Higgs Extra-dimension and new gauge bosons:
Search for high-mass resonances
Perspectives for the LHC
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 5
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 6
The Tevatron The Tevatron
Peak luminosity > 3.2 *1032 cm-
2 s-1
Integrated luminosity/week ~ 40-60 pb-1
Highest-energy accelerator currently operational
p p_
CDF
D0
Delivered: 5.1 fbDelivered: 5.1 fb-1-1
Acquired: 4.2-Acquired: 4.2-4.34.3 fb fb-1 -1
(CDF/(CDF/ DØ))
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 7
CDF and CDF and DØDØ in RunIIin RunII
D0
CDF
Took >1 years of
collisions to
get to stable high
efficiency Jan 02
Oct 08
Tevatron SensitivitiesTevatron Sensitivities
Jet cross section measurements, heavy flavor physics, inclusive W/Z
Precision measurements (Top properties, observation of rare processes...)
New Physics searches, looking for ‘the’ unexpected
Monica D'Onofrio, IFAE 8University of Oxford, 10/28/2008
Both CDF and D0 have a very rich physics program! Both CDF and D0 have a very rich physics program!
Knowledge of the SM: Knowledge of the SM: QCD and QCD and EWKEWK Test of Next-to-Leading Order
perturbative QCD inclusive jet cross section
Probing distances ~10-19 m Constrains gluon PDF at high-x
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 9
MW = 80413±48 MeV
W = 2032±73 MeV
world’s most precise single measurements!
Z(e+e-)+jets Clean signature, low background Test ground for Monte Carlo tools
W Mass and width
Knowledge of SM: Knowledge of SM: top physics top physics Top quark discovered at the Tevatron in 1995 Very extensive program on top physics:
Precision measurements of top mass Top cross sections, properties…
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 10
Mtop = 172.4 ± 0.7 (stat) ± 1.0 (syst) GeV/c2
Knowledge of SM: Knowledge of SM: rare processes rare processes
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 11
The focus is now to uncover the unknownThe focus is now to uncover the unknown
Evidence of Single top production
DiBoson cross sections
Measurements of W/Z, WW and WZ cross sections
ZZ production Evidence at CDF Observation at D0!!
D0:s + t = 4.7 ± 1.3 pb
CDF: s + t = 2.0-2.7 pb (± 0.7 pb per analysis)
Consistent with NLO calculation
Consistent with NLO calculation: 1.4 ± 0.1 pb
Needle in the haystackNeedle in the haystack Every measurement we make is
an attempt to find New Physics When searching for a needle in a
haystack, the hay is more important than the needle...
Many searches are extensions of SM measurements.
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 12
Signature-based searches Signature driven Optimize selection to
reduce backgrounds Event count; event
kinematics
Model-inspired searches Theory driven Model-dependent
optimization of event selection
Set limits on model parameters
The SM Higgs BosonThe SM Higgs Boson
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 14
SM Higgs Production and DecaySM Higgs Production and Decay Direct production gg→H
Highest Production rate Largest background
Associated production ZH/WH Leptonic vector boson decay helps for
triggering and signal extraction
• Low Mass (MH<135 GeV/c2) H→bb mode dominates WHlbb, ZHbb , ZHllbb VBF Production, VHqqbb, H(with 2jets), H, WH->WWW, ttH
• High Mass (135<MHigh Mass (135<MHH<200 GeV/c<200 GeV/c22)) H→WW mode dominates
MH (GeV/c2)
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 15
HiggsHiggs→→WWWW**→→llll Most sensitive channel for high mass Higgs
gg →H → WW* and W(Z)H → W(Z)WW*
Unbalanced transverse energy (MET) from
2 leptons: e,,→e, (must have opposite signs) Key issue: Maximizing lepton acceptance Primary backgrounds: Drell-Yan, WW
Higgs is scalar leptons travel same direction In t-channel WW, W are polarized along the beam direction
• Use Matrix Element and Neural Network methods
Analysis Lum
(fb-1)
Higgs
Event
s
Exp.
Limi
t
Obs.
Limi
t
CDF ME+NN 3.0 17.2 1.6 1.6
DØ NN 3.0 15.6 1.9 2.0
Results at mH = 165GeV : 95%CL Limits/SM
ii
iTT nEE
SM Higgs limitsSM Higgs limits
Monica D'Onofrio, IFAE 16University of Oxford, 10/28/2008
CDF/D0 combination: High mass only
Exp. 1.2 @ 165, 1.4 @ 170
GeVObs. 1.0 @ 170 GeV
Tevatron exclude at 95% C.L. the
production of a SM Higgs boson of 170 GeV
Low mass combination difficult due to ~70 channels: Expected sensitivity of CDF/DØ combined: <3.0xSM @ 115GeV
A 15 GeV window [162:177] excluded @ 90% CL
Searches Beyond SMSearches Beyond SM
Supersymmetry
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 18
SupersymmetrySupersymmetry New spin-based symmetry relating fermions and bosons:
Q|Boson> = Fermion
Q|Fermion> = Boson
HA,H,h, H,H DU
Define R-parity = (-1)3(B-L)+2s
R = 1 for SM particles R = -1 for MSSM partners
gaugino/higgsino mixing Minimal SuperSymmetric SM
(MSSM): Mirror spectrum of particles Enlarged Higgs sector: two doublets
with 5 physical states
Naturally solve the
hierarchy problem
If conserved, provides Dark Matter Candidate
(Lightest Supersymmetric Particle)
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 19
No SUSY particles found yet: SUSY must be broken More than 100 parameters even in minimal (MSSM) models
Symmetry breakingSymmetry breaking
SUSY breaking(hidden sector)
MSSM(visible sector)
gravity
Gauge fields, loop effects….
or
choose a model mSUGRA, GMSB, ….
SoftSUSY LLL
Breaking mechanism determines phenomenology and search strategy at colliders: Direct searches or subtle deviations in precision
measurements
Constrained MSSM models used as benchmark
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 20
Sparticles mass and cross sections Sparticles mass and cross sections
(p
b)
m (GeV)
T. Plehn, PROSPINO
Squarks and gluinos are heavy Sizeable Chargino/neutralino cross
sections M(+) ~ M(02) ~ 2M(0
1)
M(g) ~ 3M(+) ~
0,6tan,300
300,100
0
2/10
A
GeVmGeVm
In R parity conservation scenario,
the LSP is the neutralino ( )
in mSUGRA, new superfields in “hidden” sector Interact gravitationally with MSSM 5 parameter at GUT scale
1. Unified gaugino mass m1/2
2. Unified scalar mass m0
3. Ratio of H1, H2 vevs tanβ
4. Trilinear coupling A0
5. Higgs mass term sgn()
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 21
mSUGRA: Low tan scenario (=5 for CDF, = 3 for D0)
Assume 5-flavors degenerate
Inclusive search for squark/gluino Inclusive search for squark/gluino
A0 = 0, <0M0 [0,500 GeV/c2] m1/2 [50,200 GeV/c2]
Mq > Mg
gg final state dominates
4 jets expected
Mq ~ Mg
qg final state dominates
3 jets expected
Mq < Mg
qq final state dominates
2 jets expected
~ ~
~
~~
~~~
~~
~~
3 different analyses carried out with different jet multiplicitiesFinal selection based on Missing ET , HT = (ETjets) and ET jets
Final state: energetic jets of hadrons and large unbalanced transverse energy (due to presence of 0)
q
qq~
q
~g~
g~g~0~0~
0~0~
q
q
q
qq~
q
~
g~ 0~0~
~0
q
g
~ 0~0~
q
q~ 0~0
q
q
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 22
Background rejectionBackground rejection
Data sample CleanupData sample Cleanup
► at least one central jet with ||<1.1
► minimum missing ET of 70 GeV
► Reject beam-related backgrounds and cosmics
Rejection of SM processesRejection of SM processes
W/Z+jets with Wl or Z, DiBoson and tt production: Signatures very similar to SUSY
QCD-multijet: ET due to jet energy mismeasurement.
DiBoson
Define signal region based on selections Define signal region based on selections that maximize background rejectionthat maximize background rejection
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 23
QCD multijet rejection QCD multijet rejection Missing ET from mis-reconstructed jets
Collinear with one of the leading jets
Apply cuts on (missingET-jets)
(MET-jets) cut reversed for at least one of the leading jets
►CDF: remaining QCD-bkg estimatated from Monte Carlo. ►Control checks in enhanced QCD-sample
►DØ : QCD-bkg extrapolated in data by exponential fit function
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 24
Top and Boson+jets rejectionTop and Boson+jets rejection
Genuine Missing ET in the event
Suppressed vetoing events with: jet Electromagnetic fraction > 90%, to
reject electrons mis-identified as jets
isolated tracks collinear to missing ET to
reject undetected electrons/muons
Modeled using Monte Carlo Normalized to NLO cross section Define control regions reversing
lepton vetoes checks of background estimations Understanding these processes is
fundamental
q
g q
Z/*
g q
W
q
W
b
blq’
qt
t Control region
Control region
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 25
DATA vs SM predictionsDATA vs SM predictions
Good agreement between Observed and Expected eventsSystematic uncertainties dominated by Jet Energy scale
2 jets 3 jets 4 jets(gluino)
CDF HT>330, ET>180GeV/c2 HT>330, ET>120GeV/c2 HT>280, ET>90GeV/c2
Data 18 38 45
Expected SM
165 3712 4717
D0 HT>330, ET>225GeV/c2 HT>375, ET>175GeV/c2 HT>400,ET>100GeV/c2
Data 11 9 20
Expected SM
11.11.2 10.70.9 17.71.1
CDF DØ
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 26
Similar results for CDF and DØ
Exclusion limits: Exclusion limits: MMg g -M-Mqq and and MM00-M-M1/21/2 plane plane
For Mg=Mq → M > 392 GeV/c2
Mg > 280 GeV/c2 in any case~
~ ~
Results can be interpreted as a function of mSUGRA parameters
LEP limit improved in the region where 70<M0<300 GeV/c2 and 130<M1/2<170
GeV/c2
~~ ~~
95% C.L. Exclusion limit
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 27
Search for chargino/neutralinoSearch for chargino/neutralino
Small cross sections (~0.1-0.5 pb) Very low background:
Drell-Yan Diboson (WW, WZ/*, ZZ/*, W) Top pair production QCD-multijets, W+jets (misidentified leptons)
Lepton ET
CDF: 5 exclusive channels combinations of “tight” (t) and “loose”
(l) lepton categories 3-leptons (e,Lept) 2-leptons (e,Lept) + iso-track T (Hadr)
Ordered in terms of S/B
e,Lept, Hadr
tttttl tll ttTtlT
DØ: 4 analyses carried out ee+IsoTrk, +IsoTrk,
e+IsoTrk, Same-sign
mSUGRA 02 ±
1 pair production
Signature: three leptons and ET
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 28
0022 ±±
1 1 resultsresults
3 tight leptons selection
mSUGRA Benchmark:
m0=60 GeV/c2,m1/2=190 GeV/c2, tan=3, A0=0, >0
channelmSUGRA Signal
SM Expected DATA
Trilepton (3 channels)
4.5 0.2 0.4 0.88 0.05 0.13 1
dilepton + track
(2 channels)6.9 0.2 0.7 5.5 0.7 0.9 6
Good agreement between data and SM prediction set limit
Signal region: Missing ET > 20 GeV + topological cuts Njet=0,1 and ET
jet < 80 GeV
CDF
DØ
Data Observed : 3 SM Expected: 4.1 0.7
47 Dilepton and trilepton control regions defined to test SM predictions
(4 channels)
Excluded region in mSUGRA Excluded region in mSUGRA
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 29
Small m = m(20 )-m(l), soft leptons from 2
0 decay Loss in acceptance, no exclusion
~
excluded region in mSUGRA m0-m½ space for tan(β)=3, A0=0, μ>0
~~
m0 = 60 GeV/c2
Exclude m±
1 < 145 GeV/c2
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 30
GGauge auge MMediated ediated SSymmetry ymmetry BBreakingreaking
0
15tan
2M
1N
TeV 100
m
m
(taken from N. Ghodbane et al., hep-ph/0201233)
Snowmass p8 spectra
SUSY breaking at scale (10 -100
TeV). Mediated by Gauge Fields (“messengers”) Gravitino very light (<< MeV) and LSP Neutralino or slepton can be NLSP If NLSP is neutralino
In Rp conservation scenario: 2 NLSP 2+ MET (+X) in final state
G~~0
1
CDF Run I
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 31
+Missing E+Missing ETT Assuming 0
1 (NLSP) short-lived Very low SM background
Z , W l Understanding of instrumental
background challenging: Mis-measured ET: use multijet data sample e misidentification: use W(e) data
GeV 229)M(GeV, 125)M(
CL 95% @ TeV 91.5
1
01
3 events (SM: 1.60.4)
ET> 60 GeV
2 photons pT > 25 GeV, ||<1.1
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 32
Delayed PhotonsDelayed Photons 0
1 life-time undetermined in GMSB long-lifetime can be in ~ns range
Final state: Delayed photon+ET
+jets
c
|xx|ttt if
ifγc
tc() in [2-10] ns range
ET> 40 GeV, pT>25 GeV, ET
jet > 35 GeV ||<1.1, |(jet)|< 2.
Observed 2 events SM Expect.: 1.30.7M(0
1)>101 GeV @ 5 ns
MSSM HiggsMSSM Higgs
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 34
Neutral MSSM HiggsNeutral MSSM Higgs In MSSM, two Higgs doublets
Three neutral (h, H, A), two charged (H±) Properties of the Higgs sector largely determined by mA and tan Higher-order effects introduce other SUSY parameters
Large Higgs production cross section at large tan
Higgs decays:BR(bb) : ~90%Huge QCD background
BR ~10%
HA,H,h, H,H DU
BSM Higgs: BSM Higgs: CDF and DØ channel
pure enough for direct production search DØ adds associated production search: bb
Key issue: understanding Id efficiency Large calibration samples: W for Id
optimization and Z for confirmation of Id efficiency
No Evidence for SUSY Higgs
Limits: tan vs mA
generally sensitive at high tan
CDF:
Monica D'Onofrio, IFAE 35University of Oxford, 10/28/2008
mA=140 GeV/c2
mvis p1
vis p 2
vis p T
Searches Beyond SMSearches Beyond SMMore ‘Exotic’ models…
- Extra-Dimensions- New Gauge bosons
Search for high mass resonancesSearch for high mass resonances Di-lepton resonances have a strong track record for
discovery → J/ψ, Υ, Z Enlarge the possible final states looking also in dijet, ditop or
dibosons! Construct the pair invariant mass and look for any
excesses in the high mass spectrum
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 37
Example of di-lepton events
Transverse plane
Advantage
Sensitive to many BSM scenarios:•Extra-Dimensions•Extended SUSY-GUT groups(SO(10),E6,E8...leading to additional gauge bosons, Z' and W')•R-parity violating SUSYand more...
Extra-DimensionsExtra-Dimensions ‘Solves’ the hierarchy problem by postulating
that we live in more than 4 dimensions. Large Extra Dimensions: Arkani-Hamed,
Dimopoulos, Dvali (ADD) Gravity propagate in nd additional spatial
dimensions compactified at radius R Effective Planck scale:
no narrow resonances, SM particles pair production enriched by exchanged gravitons
Randall-Sundrum model: Only one extra dimensions (wraped) limited by two 4-dimensional brains. SM particles live in one of the brains. Graviton can travel in all 5 dimensions, appears as
Kaluza-Klein towers dimensionless coupling (k/MPl) free parameter
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 38
M2Planck ~ Rn(MD)n+2 , MD ~ 1
TeV
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 39
Search for High Mass Search for High Mass ee++ee-- / / Resonance Resonance
CDF: Central-Central (|1,2|<1) or Central-Forward (||<2) e+e- pair with ET>25 GeV
D0: EM objects pair (e+e- or ), CC: |1,2|<1.1, CF 1.5<||<2.4
Major Backgrounds: DrellYan QCD (including W+jets)
Resonance search performed in mass range 150-1000 GeV/c2
No evidence for narrow resonances set limits
CDF
Search for RS Gkk resonance
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 40
Exclusion limitsExclusion limits
Limits on extended gauge groups theories: SM-like Z’: 966 GeV/c2 Limits on effective Planck scale in LED:
Expect a cross section enhancement above SM Use , e+e-
CDF (D0) exclude RS graviton with mass below 850 (900) GeV/c2 for k/MPl=0.1
Can interpret results in term
of several other scenarios
1.29 - 2.09 TeV depending on number of ED
Di-muon resonancesDi-muon resonances Looking for narrow dimuon resonance
decaying Could have spin 0, 1 and 2
Search in 1/mμμ in which detector resolution is ~const:
17% inverse mass resolution at 1 TeV construct templates for several signal
hypothesis, add bkg and compare to data
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 41
Spin 1 Z’-like Spin 1 Z’-like limitslimits
For the first time beyond one TeV for SM-Z'!
Spin 0 (RPV sneutrinos): mass limits up to 810 GeV
Spin 2 ( RS Graviton): mass limits up to 921 GeV
and more! and more! dijet resonances
Limits on several models, up to 1.2 TeV!
ditop resonances limits on massive gluons and
leptophobic Z' (Mz' > 760 GeV) W' in tb(+c.c.) or e final state
world's best limit MW'→ e > 1 TeV
searches for t' or b' fourth generation quarks not
excluded by EWK interesting tails in t' → Wq mt' > 311 GeV
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 42
mass exclusion Model
870 GeV/c2 Excited quark
1110 GeV/c2 Color-octet technirho
1250 GeV/c2 Axigluon & coloron
630 GeV/c2 E6 diquark
Every final state is currently investigated!!!
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 43
Final remarksFinal remarks
Projected Integrated Luminosity in Run II (fb-1) vs time
0
1
2
3
4
5
6
7
8
9
10
10/1/2003
4/18/2004
11/4/2004
5/23/2005
12/9/2005
6/27/2006
1/13/2007
8/1/2007
2/17/2008
9/4/2008
3/23/2009
10/9/2009
4/27/2010
11/13/2010
time since FY04
Inte
gra
ted
Lu
min
os
ity
(fb
-1)
FY08 start
8.75 fb-1
7.29 fb-1
Highest Int. Lum
Lowest Int. Lum
FY10 start
today
~ 1.8 fb-1 delivered in FY08
Projection curves
In case we don’t find new particles @ Tevatron….
CDF and D0 have a wide and rich program of searches for SUSY. No evidence yet, but.. expect to collect and analyze up to 8 fb-1
of data in the next years.
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 44
The Future …. now almost The Future …. now almost presentpresent
ATLAS
CMS
The Large Hadron Collider (LHC)The Large Hadron Collider (LHC)
Proton- Proton Collider
7 TeV +7 TeV
First Event (9/10/2008)!
Roadmap to discoveryRoadmap to discovery
High-pT lepton resonances may provide the first signal of New Physics: Less sensitive to calorimeter
performance
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 45
100 pb-1
10 pb-1
100 pb-1
1 fb-1
time
Sensitivity to 1-1.5 TeV resonances → lepton pairs
Understand SM background for SUSY and Higgs
Jet energy scale calibration
Higgs discovery sensitivity (MH=130~500 GeV)
Explore SUSY to m ~ TeV
Precision SM measurements
Detector calibration
Use SM processes as “standard candles”
46
Jets measurements @ LHCJets measurements @ LHC
Jet energy scale largest source of systematic error initial uncertainty ~ 5-10%
Need to reduce error for QCD test
ATLAS preliminary
LHC (s = 14 TeV)
10 events with Ldt = 20 pb-1
Tevatron
measure W/Z + jet(s) cross-section
γ/Z+jets calibration signalMonica D'Onofrio, IFAE University of Oxford, 10/28/2008
Ze+e-50 pb-1
Ldt=1fb-1
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 47
SUSY@LHCSUSY@LHCExclThe LHC is built to discover SUSY
If there, we will find it relatively soon
But it will take a bit of time:• commissioning phase to understand detector performance and “re-discover” the SM pTjets+ET
miss(GeV)
ATLAS preliminary
RP-conserving mSUGRA
An example:
squark-
gluino
production
48
SM Higgs: a challenge!SM Higgs: a challenge!For low mass of ~120 GeV need to combine many channels with small S/B or low statistics (H , H→, H ZZ* 4l, H→ WW*→ll )
Required luminosity for 95% C.L. exclusion
ATLAS preliminaryH ZZ* 4l
30 fb-1
The “golden” channel
ATLASpreliminary
most promising in the range 150-180 GeV, again with H → WW* →ll
almost excluded at the Tevatron!
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 49
ConclusionsConclusions
"Whatever" is beyond the Standard Model, these are exciting times for high energy physics!
TeVat
ron?
LHC
Back upBack up
Higgs reach @ Tevatron Higgs reach @ Tevatron With 7 fb-1
• exclude all masses !!! [except real mass]• 3-sigma sensitivity 150:170 LHC’s sweet spot
7.0
This is very compelling
X2.25
Monica D'Onofrio, IFAE 52University of Oxford, 10/28/2008
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 53
mSUGRAmSUGRA
EWK GUT
1. Unified gaugino mass m1/2
2. Unified scalar mass m0
3. Ratio of H1, H2 vevs tanβ
4. Trilinear coupling A0
5. Higgs mass term sgn()
5 parameters at GUT scale
New superfields in “hidden” sector Interact gravitationally with MSSM Soft SUSY breaking
In R parity conservation scenario, the LSP is the neutralino ( )
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 54
Control regions (CDF) Control regions (CDF)
Invariant Mass (GeV/c2) 15 76 106
10
1
5
Signal?
Z + fakeDY +
Diboson
M
ET
(G
eV)
2-leptons control region
2-leptons+T MET < 10 GeV
3-leptons MET < 10 GeV
Dilepton and trilepton control regions defined to test SM predictions: function of ET and the invariant mass of the 2 leading leptons
47 in total!
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 55
CDF Jet Energy Scale CDF Jet Energy Scale Different correction factors: (frel) Relative Corrections
Make response uniform in (MPI) Multiple Particle Interactions
Energy from different ppbar interaction (fabs) Absolute Corrections Calorimeter non-linear and non-compensating (UE) Underlying Event
Energy associated with spectator partons
PT jet(R) = [ PT jetraw(R) frel (R) – MPI(R)]
fabs(R) - UE(R)
Absolute correction factor
CDF Run II
Total systematic uncertainties for JES: between 2% and 3%
Jets are composite object:•complex underlying physics•depends on detector properties
Monica D'Onofrio, IFAE University of Oxford, 10/28/2008 56
T. Plehn, PROSPINO
• Strongly interacting particles• High cross sections for gluinos and squarks production
Golden signature!
(pb)
LHC mSUGRA cross sectionsLHC mSUGRA cross sections