Physik Institut - Universität Zürich · Recent results from proton-proton collisions at CMS...

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


Introduction to CMS

3


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



5

• Calorimeters:

• ECAL: PbWO4 crystals

• HCAL: Cu + scintillator

• Muon chambers:

• Drift Tubes

• Cathode Strip Chambers

• Resistive Plate Chambers



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.



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.

decay mode!reconstructed " (s)0"" """

a.u.

0

0.2

0.4

0.6

0.8Data

! ! #Z W+jets

/ewkt tQCD

-1=7 TeV, 36 pbsCMS Preliminary 2010,

)2 visible mass (GeV/cjet!µ

20 40 60 80 100 120 140 160 180 200

num

ber o

f eve

nts

0

10

20

30

40

50

60

70Data

-! +! " *#Z/QCDW + jets

-µ +µ " *#Z/ + jetstt


)2 visible mass (GeV/cjet!µ

20 40 60 80 100 120 140 160 180 200nu

mbe

r of e

vent

s0

20

40

60

80

100

120Data

-! +! " *#Z/QCDW + jets

-µ +µ " *#Z/ + jetstt


Results on Standard Model Physics


QCD

9

Inclusive jet productioncross section

Inclusive prompt photonproduction cross section

Phys. Rev. Lett. 107 (2011) 132001 Phys. Rev. D 84 (2011) 052011

http://dx.doi.org/10.1103/PhysRevLett.107.132001

http://dx.doi.org/10.1103/PhysRevLett.107.132001

http://dx.doi.org/10.1103/PhysRevD.84.052011

http://dx.doi.org/10.1103/PhysRevD.84.052011


Electroweak

10


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

1

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

rati

o t

o P

YT

HIA

R!0 0.5 1 1.5 2 2.5 3 3.5 4

rati

o t

o P

YT

HIA

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

http://www.springerlink.com/content/v287172w5w507051/

http://www.springerlink.com/content/v287172w5w507051/

http://prl.aps.org/abstract/PRL/v106/i11/e112001




http://cdsweb.cern.ch/record/1360175/files/PhysRevD.84.052008.pdf?version=1

http://cdsweb.cern.ch/record/1360175/files/PhysRevD.84.052008.pdf?version=1

http://www.springerlink.com/content/973044328847026g/

http://www.springerlink.com/content/973044328847026g/


• 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



http://cdsweb.cern.ch/record/1369205?ln=en



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


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


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

400

500

600

700


SUSY

17

• MSSM H→tt

HIG-11-020




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


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)

http://www.sciencedirect.com/science/article/pii/S0370269311009518

http://www.sciencedirect.com/science/article/pii/S0370269311009518

http://link.aps.org/doi/10.1103/PhysRevLett.106.201802

http://link.aps.org/doi/10.1103/PhysRevLett.106.201802


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.


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


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

http://cdsweb.cern.ch/record/1376672

http://cdsweb.cern.ch/record/1376672


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

http://cdsweb.cern.ch/record/1369546/




http://arxiv.org/abs/1109.4985

http://arxiv.org/abs/1109.4985




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.


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,



(TeV)DM1 1.5 2 2.5 3

(pb)

!-210

1

210

=6"ADD,



) [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

""#Z

"l#W

tt

QCD-l+l#Z

Data

CMS Preliminary

=7 TeVs at -1

L dt = 1.1 fb$

)2

, Jet1

(Jet!"0 0.5 1 1.5 2 2.5 3 3.5

Eve

nts

/ 0

.11

10

210

310

410

510

2#2DADD M

$$%Z

$l%W

tt

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

Eve

nts

/ 2

5 G

eV

1

10

210

310

410

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




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


= 0.05k~ KKG95% CL limitCMS Preliminary

at 7 TeV-11.1 fb

[GeV]1M600 800 100012001400160018002000

[pb]

!R

S gr

avito

n

-210

-110


= 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

-110

1

10

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




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






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




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




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




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

210

310

410

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

10

210

310

410

510

DATA

-µ+µ!*"Z/


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


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


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




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.

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EXO-11-022

EXO-11-020






Model-independent Searches

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• 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






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:

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https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults



Physik Institut - Universität Zürich · Recent results from proton-proton collisions at CMS...

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