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Recent results from proton-proton collisions at CMS
Ernest Aguiló
Physik Institut - Universität Zürich
LPHE, Lausanne, Oct. 31st 2011
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Outline
2
• Introduction to CMS
• Detector performance
• Results on Standard Model Physics: • QCD
• Electroweak
• B-Physics
• Top
• Higgs
• Results on Physics beyond the SM: • SUSY
• Heavy bosons
• Fourth generation
• Leptoquarks
• Extra dimensions
• Model-independent searches
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Introduction to CMS
3
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Detector Performance
4
• Tracker:
• Pixels (1440 sensors, 66M pixels)
• 3 barrel layers, 2 discs / end cap
• Size: 100 x 150 µm2
• Strips (15148 sensors)
• 10 barrel layers, 12 discs / end cap
• Width: 320 - 500 µm
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Detector Performance
5
• Calorimeters:
• ECAL: PbWO4 crystals
• HCAL: Cu + scintillator
• Muon chambers:
• Drift Tubes
• Cathode Strip Chambers
• Resistive Plate Chambers
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Detector Performance
6
Operational channelsOperational channelsRPC 98.5%DT 99.4%CSC 98.3%HB 99.9%HE 100.0%HF 99.9%ES 95.9%EE 98.6%EB 99.1%STRIP 97.8%PIXEL 96.9%
• Trigger & DAQ:
• L1 Trigger: 100kHz maximum rate. Uses multi-object algorithms.
• HLT: 300Hz maximum rate. Single object + >200 multi-object triggers. Mitigates pile-up.
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Detector Performance
7
• Particle Flow:
• Use information from all the sub-detectors to build 5 kinds of particles: muons, electrons, photons, charged and neutral hadrons.
• Use these to build jets, taus and MET. Systematics greatly reduced.
• B-Tagging:
• Used to identify b-jets.
• Uses track IP’s, SV’s & soft leptons.
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a.u.
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-1=7 TeV, 36 pbsCMS Preliminary 2010,
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10
20
30
40
50
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-! +! " *#Z/QCDW + jets
-µ +µ " *#Z/ + jetstt
-1=7 TeV, 36 pbsCMS Preliminary 2010,
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vent
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40
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-! +! " *#Z/QCDW + jets
-µ +µ " *#Z/ + jetstt
-1=7 TeV, 36 pbsCMS Preliminary 2010,
Results on Standard Model Physics
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
QCD
9
Inclusive jet productioncross section
Inclusive prompt photonproduction cross section
Phys. Rev. Lett. 107 (2011) 132001 Phys. Rev. D 84 (2011) 052011
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Electroweak
10
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
B-Physics
11
• Quarkonia: cross-section, B-fraction.
• Inclusive cross-sections and angular correlations.
• Exclusive cross-sections (B+, B0, Bs).
R!0 0.5 1 1.5 2 2.5 3 3.5 4
rati
o t
o P
YT
HIA
> 56 GeV) T
JetData (p
> 84 GeV) T
JetData (p
> 120 GeV)T
JetData (p
Normalisation region
PYTHIAMadGraph
MC@NLO
Cascade
-1 = 7 TeV, L = 3.1 pbsCMS
0
1
2
3
40
1
2
3
40
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2
3
4
| < 3.0Jet"|
| < 2.0B" > 15 GeV, |B
Tp
R!0 0.5 1 1.5 2 2.5 3 3.5 4
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HIA
R!0 0.5 1 1.5 2 2.5 3 3.5 4
rati
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Eur.Phys.J. C71 (2011) 1575
Phys. Rev.Lett. 106:112001(2011)Phys. Rev. Lett. 106:252001(2011)
Phys. Rev. D 84:052008 (2011)
JHEP 1103 (2011) 136
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
• Re-discovered single top with only 36 pb−1
• Measurement of the pair cross-section at 7 TeV
• Properties:
• Mass
• Mass difference
• Charge asymmetry
Top
12
Phys. Rev. Lett. 107 (2011) 091802
TOP-11-014
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Higgs
13
• H → WW: High sensitivity but low resolution (~30 GeV).
• H → gg: Low sensitivity, high resolution (1-2 GeV). Challenging with increasing pile-up.
• H → ZZ: Low sensitivity, high resolution (1-2 GeV) at low masses.
• Other channels: H → tt; associated production (VH → Vbb).
HIG-11-022
Results on Physics Beyond the SM
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
SUSY
• Every SM particle has its super-partner with 1/2 difference in spin.
• Dominant at the LHC: squark-gluino associated production.
• Searches:
• All hadronic + MET
• Leptons (SS or OS) + jets + MET
15
All hadronic + MET
SS leptons
T!0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
Even
ts /
0.02
5
-110
1
10
210
310
410
CMS Preliminary 2011
= 7 TeVs, -1 L dt = 1.1 fb" = 7 TeVs, -1 L dt = 1.1 fb"DataStandard ModelQCD MultiJet
, W, Z + JetsttLM4LM6
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
SUSY
16
)2 (GeV/c0m0 200 400 600 800 1000
)2 (G
eV/c
1/2
m
200
300
400
500
600
700
(250)GeVq~
(250)GeVg~
(500)GeVq~
(500)GeVg~
(750)GeVq~
(750)GeVg~
(1000)GeVq~
(1000)GeVg~
(1250)GeVq~
(1250)GeVg~
T!
Jets+MHT
SS Dilepton
OS Dilepton
MT21 Lepton
-1 = 7 TeV, Ldt = 1.1 fbs "CMS Preliminary
> 0µ = 0, 0
= 10, A#tan
<0µ=5, #tan, q~, g~CDF <0µ=3, #tan, q~, g~D0
±
1$%LEP2 ±l~LEP2
= L
SP&%
2011 Limits
2010 Limits
)2 (GeV/c0m0 200 400 600 800 1000
)2 (G
eV/c
1/2
m
200
300
400
500
600
700
)2 (GeV/c0m0 200 400 600 800 1000
)2 (G
eV/c
1/2
m
200
300
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700
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
SUSY
17
• MSSM H→tt
HIG-11-020
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Leptoquarks
• Why leptoquarks?
• Remarkable symmetry between the 3 generations of quarks and leptons.
• It’s natural to predict (GUT, compositeness, technicolor) particles that carry both baryon and lepton number.
• Properties:
• Color-triplet bosons with weak isospin,
• Can have spin 0 (scalar) or 1 (vector),
• Fractional electric charge,
• Couple to a quark and a lepton via Yukawa coupling λ, different for right/left handed,
• Coupling to one generation only assumed due to absence of FCNC.
• At the LHC expected to be produced in pairs from gluons (they have color!).
18
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Leptoquarks
19
[GeV]LQM200 250 300 350 400 450 500
β
00.10.20.30.40.50.60.70.80.9
1
[GeV]LQM200 250 300 350 400 450 500
β
00.10.20.30.40.50.60.70.80.9
1
)-1 exclusion (1 fb∅D)-1eejj 95% CL limit (obs., 33.2 pb
)-1jj 95% CL limit (obs., 36 pbνeCombined 95% CL limit (obs.)Combined 95% CL limit (exp.)
CMS = 7 TeVs
eejj
jjνe
• So far in CMS only 34 pb−1:
• 1st generation LQ search: eejj & enjj channels combined.
• 2nd generation LQ serach: only mmjj channel.
Physics Letters B 703:3(2011) 246 Phys. Rev. Lett.106:201802 (2011)
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Fourth Generation
20
• Why 4th generation? mn>45 GeV does not contradict LEP.
• 4x4 CKM matrix accomodates Belle & D∅ new physics results + matter/anti-matter asymmetry
• With a 4th generation:
• successful unification of gauge couplings, hierarchy problem solved.
• Higgs mass less constrained by electroweak precision measurements.
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Fourth Generation
• Mt’ - Mb’ < MW favored by electroweak measurements then look for t’ → bW. In this analysis both W → ln.
• Select two isolated leptons with pT > 20 GeV, two jets with pT > 30 GeV (not matched to leptons, at least one b-tagged) and MET > 30 GeV. Cut Z mass window.
• Signal region: both Mlb > 170 GeV.
• Systematics: b-tagging (10%), trigger (2%), lepton selection (2%), jet & MET energy scale (8%), luminosity (4.5%).
21
)2 (GeV/cl1b1Generated M0 100 200 300 400 500
)2 (G
eV/c
l2b2
Gen
erat
ed M
0
100
200
300
400
500
CMS Simulation)2=350 GeV/c
t' (Mt't'
tt
)2 (GeV/cl1b1Reconstructed M0 100 200 300 400 500
)2 (G
eV/c
l2b2
Rec
onst
ruct
ed M
0
100
200
300
400
500
CMS Simulation)2=350 GeV/c
t' (Mt't'
tt
Table 3: Summary of the observed and predicted yields. Uncertainties include both statistical andsystematic errors, apart from for di-boson and single top where uncertainties are statistical only.
Sample Yield Sourcett̄ → �+�− 1.35 ± 0.67 DataFake leptons 0.0+0.4
−0.0 DataDY→ e+e− or µ+µ− 0.07+0.13
−0.07 DataDY→ τ+τ− 0.11 ± 0.11 SimulationDi-boson 0.02 ± 0.02 SimulationSingle top 0.07 ± 0.04 SimulationTotal prediction 1.62+0.80
−0.70
Data 1
Since no excess beyond the SM background is found, 95% C.L. upper limits on the production cross135
section of t�t̄� as a function of t� mass are set, using the CLs method [23, 24].136
The limit calculation is based on the information provided by the observed event count combined with the137
values and the uncertainties of the luminosity measurement, the background prediction, and the fraction138
of all t�t̄� events expected to be selected. This fraction is the Efficiency × Acceptance × Branching Ratio139
for simulated signal events, and is given in Table 4 for different values of Mt� .140
Table 4: Efficiency × Acceptance × Branching Ratio in simulated events for different t� masses. Eachvalue has a relative uncertainty of 22%.
Sample Eff×Acc×BRt�t̄�, Mt� = 350GeV/c2 0.24%t�t̄�, Mt� = 400GeV/c2 0.33%t�t̄�, Mt� = 450GeV/c2 0.41%t�t̄�, Mt� = 500GeV/c2 0.50%t�t̄�, Mt� = 550GeV/c2 0.55%t�t̄�, Mt� = 600GeV/c2 0.58%
The calculated limits are shown in Figure 3 and Table 5. As a conclusion, the expected and observed141
95% C.L. lower bounds on the t� mass are 415 GeV/c2 and 422 GeV/c2 respectively from the analysis of142
a data sample corresponding to an integrated luminosity of 1.14 fb−1.143
Table 5: The expected theoretical cross section of t�t̄� production and the 95% C.L. upper limits on theproduction cross section of t�t̄�.
Mt� 350 GeV/c2 400 GeV/c2 450 GeV/c2 500 GeV/c2 550 GeV/c2 600 GeV/c2
Theory (pb) 2.940 1.301 0.617 0.310 0.162 0.088Expected (pb) 1.517 1.103 0.888 0.728 0.662 0.628Observed (pb) 1.406 1.022 0.823 0.675 0.613 0.582
References144
[1] P.H. Frampton, P.Q. Hung and M. Sher, Phys. Rept. 330 (2000).145
[2] G.D. Kribs, Phys. Rev. D 76, 075016 (2007).146
[3] W.-S. Hou, Chin. J. Phys. 47 (2009).147
[4] B. Holdom et al., PMC Phys. A 3 (2009).148
5
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Fourth Generation
• No excess beyond SM.
• 95% CL Limits:
• expected: Mt’ > 415 GeV
• observed: Mt’ > 422 GeV
22
2 > 170 GeV/cl1b1
) for M2 (GeV/cl2b2M0 100 200 300 400 500
Even
ts
-210
-110
1
10
210
Data
(dileptonic)tt
Other backgrounds
2 = 350 GeV/ct'
, Mt't'
CMS Preliminary=7 TeVs at -11.14 fb
µ/eµµEvents with ee/
Signal Region
2 > 170 GeV/cl2b2
) for M2 (GeV/cl1b1M0 100 200 300 400 500
Even
ts
-210
-110
1
10
210
Data
(dileptonic)tt
Other backgrounds
2 = 350 GeV/ct'
, Mt't'
CMS Preliminary=7 TeVs at -11.14 fb
µ/eµµEvents with ee/
Signal Region
)2 (GeV/ct'M400 500 600
') pb
t t'
! (p
p "
-110
1
10
=7 TeVs -1CMS Preliminary 1.14 fb
NLO Theory Expected Limitss95% CL Observed Limitss95% CL
" 1± sCL" 2± sCL
EXO-11-050
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Fourth Generation
• Other searches:
23
]2 [GeV/cb'M350 400 450 500 550
') [p
b]b
b'
!(p
p "
-110
1
10 Prediction
expected limitobserved limit
2 > 495 GeV/cb'Limit at 95% CL: M
"2 "1
= 7 TeVs -1CMS 2011 Preliminary 1.14 fb
350 400 450 5000
1
2
3
[GeV]t'M
[pb]
!
CMS preliminary µ
A0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
)2 (G
eV/c
b' =
mt'
m
350
400
450
500
550
600 = 7TeVs -1CMS Preliminary L = 1.1fb
> 0
.77
@ 9
5% C
.L. (
Teva
tron)
tbV
expected limit 95% C.L.
observed limit 95% C.L.
! 1 ±
EXO-11-051
EXO-11-054
arXiv: 1109.4985 (hep-ex)
EXO-11-036
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Extra Dimensions
24
• Hierarchy Problem:
• SM interactions can be unified at the energy scale of 1016 GeV.
• GN << a: gravity too weak to be unified at the same scale.
• Natural energy scale: Planck scale (MP = 1.2×1019 GeV).
• Possible solution: extra dimensions.
• ADD model (Arkani-Hamed, Dimopoulos and Dvali):
• n “large” extra-dimensions of size d >> 1/MP. At short distances F ~ 1/r2+n. Then MP2 ~ MD2+ndn.
• For 1 TeV scales d ~ 1 mm if n=2.
• RS-I model (Randall and Sundrum):
• one “wrapped” extra-dimension.
• From both massive Kaluza Klein gravitons appear.
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Extra Dimensions
• ADD: emission of a KK graviton. Signature: 1 jet + MET
• Selection: 1 or 2 jets, pT(j1)>110 GeV, |h(j1)|<2.4, pT(j2)>30 GeV, Df(j1,j2) < 2
25
(TeV)DM1 1.5 2 2.5 3 3.5 4
(pb)
!
-110
1
10
210
=2"ADD,
95% CL Expected limits95% CL Observed limitsTheor. prediction (LO)Theor. prediction (NLO)
CMS Preliminary-1=1.1 fbint=7 TeV, Ls
(TeV)DM1 1.5 2 2.5 3
(pb)
!
-110
1
10
210
=4"ADD,
95% CL Expected limits95% CL Observed limitsTheor. prediction (LO)Theor. prediction (NLO)
CMS Preliminary-1=1.1 fbint=7 TeV, Ls
(TeV)DM1 1.5 2 2.5 3
(pb)
!-210
1
210
=6"ADD,
95% CL Expected limits95% CL Observed limitsTheor. prediction (LO)Theor. prediction (NLO)
CMS Preliminary-1=1.1 fbint=7 TeV, Ls
) [GeV/c]1
(JetT
p0 100 200 300 400 500 600 700 800
Eve
nts
/ 2
5 G
eV
/c
1
10
210
310
410
510
610 2!2DADD M
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"l#W
tt
QCD-l+l#Z
Data
CMS Preliminary
=7 TeVs at -1
L dt = 1.1 fb$
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, Jet1
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.11
10
210
310
410
510
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$$%Z
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QCD-l+l%Z
Data
CMS Preliminary
=7 TeVs at -1
L dt = 1.1 fb&
[GeV] TmissE
200 300 400 500 600 700 800
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nts
/ 2
5 G
eV
1
10
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510
6102!2DADD M
""#Z
"l#W
tt
QCD-l+l#Z
Data
CMS Preliminary
=7 TeVs at -1
L dt = 1.1 fb$
EXO-11-059
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Extra Dimensions
• Di-photons:
• Off-shell ADD KK graviton
• On-shell RS-I KK graviton
26
[GeV]1M600 800 100012001400160018002000
[pb]
!R
S gr
avito
n
-210
-110
median expected68% expected95% expected
= 0.01k~ KKG95% CL limitCMS Preliminary
at 7 TeV-11.1 fb
[GeV]1M600 800 100012001400160018002000
[pb]
!R
S gr
avito
n
-210
-110
median expected68% expected95% expected
= 0.05k~ KKG95% CL limitCMS Preliminary
at 7 TeV-11.1 fb
[GeV]1M600 800 100012001400160018002000
[pb]
!R
S gr
avito
n
-210
-110
median expected68% expected95% expected
= 0.10k~ KKG95% CL limit
CMS Preliminary at 7 TeV-11.1 fb
[GeV]!!M200 300 400 500 600 700 800 900 1000
Entri
es/2
0 G
eV-310
-210
-110
1
10
210ObservedDiphoton+jet!
DijetSyst. Uncertainty
CMS Preliminary
at 7 TeV-11.1 fb
[GeV]!!M200 300 400 500 600 700 800 900 1000
Entri
es/2
0 G
eV-310
-210
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1
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210
[GeV]!!M200 400 600 800 1000 1200 1400 1600 1800 2000
Even
ts/2
0 G
eV
-310
-210
-110
1
10
210 = 750 GeV
1 = 0.1, Mk~
= 1000 GeV1
= 0.1, Mk~
= 1250 GeV1
= 0.1, Mk~
= 1500 GeV1
= 0.1, Mk~
= 1750 GeV1
= 0.1, Mk~
= 2000 GeV1
= 0.1, Mk~
CMS Simulation
EXO-11-038
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Extra Dimensions
27
(TeV)DM1 1.2 1.4 1.6 1.8 2
Cro
ss s
ectio
n (fb
)
10
210
310
95% CL Obs. Limit95% CL Exp. Limit
Exp. Limit!1± Exp. Limit!2±
CMS Preliminary = 7 TeVs
-1 Ldt = 1.14 fb"
n=4, Theory NLOn=4, Theory LOn=6, Theory NLOn=6, Theory LO
• Photon + MET
• Di-muon
EXO-11-058
EXO-11-039
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Heavy Bosons
• Many theories predict the existence of heavier gauge bosons W’ and Z’:
• Sequential Standard Model
• GUT’s
• Extra Dimensions (KK bosons)
• Little, Littlest Higgs Model
• Technicolor
• Typical decays:
• Z’ to quark or lepton pair (even top pair)
• W’ to lepton neutrino or quarks (even bt)
• W’ to WZ
• WR → nR
28
)2 Invariant Mass (TeV/ctt1 1.5 2 2.5 3
) (pb
)t t
! B
R(Z
' "
Z'#
Upp
er L
imit
-110
1
10
210 = 7 TeVs at -1CMS Preliminary, 886 pbCombined type 1+1 & 1+2
Observed (95% CL)Expected (95% CL)
Expected# 1±
Expected# 2±
KK Gluon, Agashe et alTopcolor Z', 3.0% width, Harris et alTopcolor Z', 1.2% width, Harris et al
CMS top pair search:
• All-jets decay channel• Divide event in 2 hemispheres• Type 1: 3 sub-jets merged in one• Type 2: The 2 W sub-jets merged in
one + 1 b-jetEXO-11-006
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Heavy Bosons
29
• W’ → en / W’ → mn
• 0.4 < pT(e/m)/MET < 1.5
• Df(e/m,MET) > 2.5
• Limits from fits to MT distributions
[GeV]TM200 400 600 800 1000 1200 1400
Even
ts /
10 G
eV
-210
-110
110
210
310
410
510
610
710 ! µ "W
WW, WZ, ZZ
+ single-toptt
QCDµµ "Z
!# "W
## "Z
Data=1.5 TeV)
W'W' (m
CMS Preliminary-1 L dt = 1.13 fb$
= 7 TeVs
! µ "W'
over
flow
bin
[GeV]TM200 400 600 800 1000 1200 1400
Even
ts /
10 G
eV
-210
-110
110
210
310
410
510
610
710
[GeV]TM200 400 600 800 1000 1200 1400
Even
ts /
10 G
eV
-210
-110
110
210
310
410
510
610
710 DibosonTTJets+SingleTop
DY->ll!"W->!µW->
+Jets#
QCD
!W->e
Data=1.5 TeV)
W'W' (m
CMS Preliminary-1 L dt = 1.03 fb$
= 7 TeVs! e %W'
over
flow
bin
W' mass (GeV)1400 1600 1800 2000 2200 2400
) (pb
)!
+
µ e
/ "
BR
(W'
. #
-310
-210
-110
CMS Preliminary = 7 TeVs
-195% Observed Limit Electron 1.03 fb
-195% Observed Limit Muon 1.13 fb
95% Observed Combined
95% Expected Combined
Theoretical Cross Section
W' mass (GeV)1400 1600 1800 2000 2200 2400
) (pb
)!
+
µ e
/ "
BR
(W'
. #
-310
-210
-110
EXO-11-024
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Heavy Bosons
30
(GeV)WZM0 200 400 600 800 1000 1200
Even
ts / 1
0 G
eV
-210
-110
1
10
210
CMS Preliminary 2011 = 7 TeVs-1L dt = 1.15 fb!
Data W+JetsVV ttZ+Jets "3l#WZW' 600
(GeV)T
Lepton Pt Sum: H0 100 200 300 400 500 600 700 800
Even
ts /
10 G
eV
-210
-110
1
10
210
CMS Preliminary 2011 = 7 TeVs-1L dt = 1.15 fb!
Data W+JetsVV ttZ+Jets "3l#WZW' 600
(GeV)WZM300 400 500 600 700 800 900
BR
(pb)
! "
-310
-210
-110 W' Limit = 784 GeV
CMS Preliminary 2011 = 7 TeVs-1L dt = 1.15 fb#
Obs. LimitExp. Limit" 1±" 2±
W'"
• W’ → WZ
• Z: pT(m,m) < (15,15) GeV; pT(e,e) < (20,10) GeV
• W: pT(m/e) > 20 GeV; MET > 30 GeV
• Optimize HT cut for each signal MC mass
EXO-11-041
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Model-independent Searches
• Resonance decaying to dileptons:
• pT > 35 GeV (40 GeV for ee in EC)
• Vertex with 4 tracks + cosmic protection
• Main bakground: Drell-Yan (MC)
• ttbar & QCD estimated from data
31
) [GeV]eem(200 400 600 800 1000 1200
Eve
nts
/ 5 G
eV
-310
-210
-110
1
10
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510
DATA
-e+e!*"Z/
+ other prompt leptonstt
jets (data)
-1 L dt = 1.1 fb# = 7 TeV sCMS preliminary
) [GeV]-µ+µm(200 400 600 800 1000 1200
Eve
nts
/ 5 G
eV
-310
-210
-110
1
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510
DATA
-µ+µ!*"Z/
+ other prompt leptonstt
jets
-1 L dt = 1.1 fb# = 7 TeV sCMS preliminary
) [GeV]-µ+e/-e+µm(200 300 400 500 600 700 800 900
Eve
nts
/ 20
GeV
-210
-110
1
10
210 DATA
+ other prompt leptonstt
jets
-1 L dt = 1.1 fb! = 7 TeV sCMS preliminary
500 1000 1500 20000
0.1
0.2
0.3
0.4
M [GeV]
-4 1
0!
"R
median expected68% expected95% expected
SSMZ'
#Z'
=0.1Pl
M k/KK
G=0.05
PlM k/
KKG95% C.L. limit
-1dt = 1.1fbL $CMS preliminary, -µ+µee+EXO-11-019
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Model-independent Searches• Heavy Stable Charged Particles:
• Using detector information:
• Tracker: dE/dx and p compatible with slow.
• Muons: time of flight.
• Stopped HSCP:
• Created at collision, decays later.
• Dedicated trigger to select bunch crossings with no collisions. 1 jet pT > 70 GeV.
32
EXO-11-022
EXO-11-020
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Model-independent Searches
33
• Other searches:
• Long lived resonances decaying to leptons:
• H → XX → 4 displaced leptons.
• Bs(d) → mm (rare b-decay):
• BR < 1.9×10−8 (4.6×10−9)
• 1.2(0.3) s away from BG only hypothesis.
• Combination with LHCb: BR>1.1×10−8 ~ 3×SM
EXO-11-004
BPH-10-019
Ernest Aguiló (UniZh) LPHE, Oct. 31st 2011
Conclusions
• CMS has shown an excellent performance since start-up in 2009.
• SM physics results in agreement with expectation.
• Wide range of beyond the SM searches. None found... yet. Tevatron sensitivity surpassed.
• I had to leave out many results:
34
https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults