searches for supersymmetry at the tevatron

Searches for Searches for Supersymmetry at the Supersymmetry at the

TevatronTevatron

Giulia Manca, University of Liverpool

Liverpool HEP SeminarThursday 15th December 2005

“Supersymmetry”, by Karl Hager

From the artist’s websitehttp://www.cassetteradio.com/cubagallery/hagen.htm

“…I try to leave the intention minimized while maintaining an element of exploratory desperation.”

http://www.cassetteradio.com/cubagallery/hagen.htm

15th December 2005 Giulia Manca, University of Liverpool

3 OutlineOutline

•Supersymmetry

•The Tevatron and its experiments

•Searching for Chargino and Neutralino

•Conclusions •Outlook


4Supersymmetry: Supersymmetry: IntroductionIntroduction

• New symmetry fermions-bosons: SM fermion SUSY boson SM boson SUSY fermion

• Ideated to cancel quadratic divergencies in the Higgs self coupling energy

• Sparticles not observed in nature => Susy must be broken!

H H

f

f

H H

f

f~

~


5 Supersymmetry: modelsSupersymmetry: models• Different mechanisms of susy breaking lead to different models

Model Name Breaking mechanism and

scale

Parameters

MSSM Minimal Supersymmetric Standard Model

>100

mSugra,cMSSM

Minimal SupergravityConstrained MSSM

Gravity (GUT) M0,M1/2,A0,tan

sgnor

GMSB Gauge Mediated Symmetry Breaking

Gauge messengers (10 TeV)

m,Mm, tan, N5, sgn(), Cgrav

AMSB Anomaly Mediated Symmetry Breaking

“conformal anomaly”

M3/2,m0(other term),tansgn

Determines the SUSY Mass spectrum!


6

G~G

Supersymmetry: particlesSupersymmetry: particles

2sLBp 1)(R ++−=R-Parity Quantum

Number->

+1 (SM particles)

-1 (Susy particles)

3. Rp (RPV): LSP decays into SM particles

i

i4 neutralinos

2 charginos

1. mSugra and AMSB: LSP, stable 2. GMSB: G LSP,stable

~


7 Supersymmetry: why ?Supersymmetry: why ?•Solves “Hierarchy Problem”

•Provides Grand Unification Theory at the 1016 GeV scale

•Consistent with results from Precision Data fits

New Top Mass172.7

GeV/c2

•Rp Conserving models provide good Dark Matter

Candidate (LSP)


8Supersymmetry & Supersymmetry & Dark Dark

MatterMatter

M1/2

(GeV)

M0(GeV)

• Evidence for Dark Matter galaxy rotation fluctuations in the cosmic

microwave background (WMAP)

• In mSugra and with Rp conserved and EW radiative corrections, 4 main regions where neutralino fulfills the WMAP relic density

•bulk region (low m0 and m1/2)

•stau coannihilation region m mstau

•hyperbolic branch/focus point (m0 >> m1/2)

•funnel region (mA,H 2m)


9Supersymmetry & Supersymmetry & Dark Dark

MatterMatter

M1/2

M0

•bulk region (low m0 and m1/2)

•stau coannihilation region m mstau

•funnel region (mA,H 2m)

•hyperbolic branch/focus point (m0 >> m1/2)

H. Baer, A. Belyaev, T. Krupovnickas, J. O’Farrill,

JCAP 0408:005,2004

HOWEVER: MORE OPTIONS WITH LESS CONSTRAINED

MODELS

• Evidence for Dark Matter galaxy rotation fluctuations in the

cosmic microwave background (WMAP)

• In mSugra and with Rp conserved and EW radiative corrections, 4 main regions where neutralino fulfills the WMAP relic density


10

Wide range of signatures: look for SuSy specific signatures or

excess in SM ones; examples:

Supersymmetry: how ?Supersymmetry: how ?

Large Missing Energy ET

Isolated leptons

Multijets

Diphotons

:

€

˜ q ˜ g GMSB:

2 LSPs

Rp : LSP

10101212

1010

101044

(fb)(fb)

Remember : VERY SMALL cross sections !!


11 The TevatronThe Tevatron

p p at ECM 1.96 TeV

• High Luminosity Tevatron 1 fb-1!

• CDF and D0 running at high efficiency

Mar01-Jul04

350pb-1

design goal

base goal

Still long way to go!

Charginos and Charginos and NeutralinosNeutralinos


13 Why Charginos and Why Charginos and Neutralinos ?Neutralinos ?

•They are light (~ 100-500 GeV/c2) Squarks and gluinos too heavy for the Tevatron

•They decay giving striking signaturesIn mSugra : 3 isolated leptons + ET

In GMSB : 2 photons + ET

In AMSB : long-lived particlesIn Rp models : >3 leptons

(and many more signatures in each model depending on the parameters !)

/

/

/


14

Higgsinos and gauginos mix

CHARGINOS NEUTRALINOS

pp

~

1±

~02

~01

~01

l

l

l

ν

Low background Easy to trigger

LOW MODEL DEPENDENCE

Striking signature at Hadron Collider,

THREE LEPTONSIn mSUGRA Rp conserved scenario,LARGE MISSING TRANSVERSE ENERGY

from the stable LSP+ν

The trilepton signalThe trilepton signal

GOLDEN SIGNAL AT THE TEVATRON !!


15 Existing Limits : LEPExisting Limits : LEP

Theoretically forbidden

LEP I Precision measurements

Chargino-Limits

Slepton Limits

SM Higgs Limits

(i.e. M1(GUT)=M2(GUT)=M3(GUT)=m1/2)


16 ADLO exclusion plotsADLO exclusion plots


17 Chargino-Neutralino Chargino-Neutralino production… production…

~02

~

1±

W*

q

q

t-channel interferes destructive

ly

q

'q

~

q

~02

~

1±

Low cross section (weakly produced)

100 150 200 250 300 350 400 450 500

10-3

1

10-2

10-1

10 SUSY (pb) vs sparticle mass(GeV/c2) for

√s=1.96 TeV

T. Plehn, PROSPINO

Tevatron sensitive to the BULK region in WMAP data


18 ……and decayand decay

~01

~02

Z*l

l

~02

l

l~

l ~01

~

1±

ν

l~

l ~01

~

1±

l

ν~

ν ~01

~01~

1±

W*ν

l

Leptons of 1st, 2nd generation

are preferred

Leptons of 3rd generation

are preferred

Best reach for the Tevatron for mass sleptons~mass

chargino=> BR (3l) enhanced

Chargino Decay

Neutralino Decay

Trileptons at CDFTrileptons at CDF


20 How to investigate How to investigate thethe different different scenarios?scenarios?

Low tan

region

High tan

region

sensitive to leptonic

decay

sensitive to hadronic decay

CHANNEL STATUS TRIGGER PATH

+ e/ reported High pT Single Lepton

ee +/e reported High pT Single Lepton

+ e/ Ongoing Low pT Dilepton

e + e/ Ongoing High pT Single Lepton

e + e/ Ongoing Low pT Dilepton

e + track

Ongoing Low pT Dilepton

e + track

Ongoing Low pT Dilepton

ee + track

reported Low pT Dilepton

Low tan scenario tan=5 , 38%

High tan scenario tan=20, 100%

Acceptanceimprovement

High pT data-sample benchmark

to understand low pT data-sample


21 Event kinematicEvent kinematic

Chargino and Neutralino

prompt decay

Leptons

separated in space

EWK rangeTypical SUSY leptons

Leading leptonNext-To-Leading lepton

Third lepton

Lepton pT (GeV)

)()( 01

02 mm −≡Δ∝ mp T

Lepton pT thresholds

trilepton analyses 20,8,5 GeV

dielectron + track analysis 10,5,4 GeV


22

Missing Transverse Energy(MET)

e

Finding SUSY at CDF Finding SUSY at CDF CENTRAL REGION

Had Calorimeter

Muon system

Drift chamber

Em Calorimeter

=0=1

Recover loss in acceptance due to cracks

in the detector if we accept

muons with no hits in the Muon Chamber

Real MET Particles escaping detection ()

Fake MET Muon pT or jet ET mismeasurementAdditional interactionsCosmic ray muonsMismeasurement of the vertex


23 Backgrounds Backgrounds

HEAVY FLAVOUR PRODUCTION

Leptons mainly have low pT

Leptons are not isolated

MET due to neutrinos

DRELL YAN PRODUCTION + additional lepton

Leptons have mainly high pT

Small MET

Low jet activity

DIBOSON (WZ,ZZ) PRODUCTION

Leptons have high pT

Leptons are isolated and separated

MET due to neutrinos

irreducible background

e

ν

pp

ee

pp

The third lepton

originates from

conversion

pp

0 The third lepton is a fake lepton

e

e

BackgroundsBackgrounds


24 Analysis StrategyAnalysis StrategyCOUNTING EXPERIMENTCOUNTING EXPERIMENT

• Optimise selection criteria for best signal/background value;

• Apply selection criteria to the data

• Define the signal region and keep it blind

•Test agreement observed vs. expected number of events in orthogonal regions (“control regions”)

•Look in the signal region and count number of SUSY events !! Or set limit on the model


25Selection criteria: (I) Selection criteria: (I)

MassMassRejection of J/,

and ZDimuon events

Mll<76 GeV & Mll>106 GeV

Mll> 15 GeV

min Mll< 60 GeV

(dielectron+track analysis)

# d

imu

on

pai

rs


26(II) DeltaPhi(l,l) + Jet (II) DeltaPhi(l,l) + Jet

vetovetoAnalysis

Kinematic Variable

Kinematic Cut

Trilepton analyses

Jet ET > 20 GeV

n. Jets < 2

Dielectron + track

analysisHT= ∑jetETj

HT < 80 GeV

Rejection of DY and high jet multiplicity

processes


27 (III) MET selection(III) MET selection

…Still BLIND !

Kinematic CutExample SUSY Signal

TOT BACKGROUND

Number of trilepton events

0.480.02

2.850.27

Invariant Mass0.420.0

21.060.18

Jet Multiplicity

0.420.02

1.040.18

MET0.370.0

20.090.03

Trilepton Analysis (muon based) L=346 pb-1

Further reducing DY by MET > 15 GeV


28Understanding of the Understanding of the

DataDataEach CONTROL REGION is investigated with different jet multiplicity to check NLO processes with 2 leptons requirement (gain in statistical power) with 3 leptons requirement (signal like topology) Control

Region with 2

Total predicted background

Observed data

Z veto, high MET, n. Jets < 2

522 79 538

Z mass, high MET, n. Jets >

1

1.9 0.9 2

Z mass window

3178 541 3168

Trilepton Analysis (muon based) L=346 pb-1

Invariant Mass 15 76 106

10

15

??

Z + fakeDY +

Diboson M

ET

SIGNAL REGION

Very good agreement between SM prediction and observed data


29 Systematic uncertaintySystematic uncertainty

Major systematic uncertainties affecting the measured number of events

Signal

Lepton ID 5%

Muon pT resolution 7%

Background

Fake lepton estimate method 5%

Jet Energy Scale 22%

Common to both signal and background Luminosity 6% Theoretical Cross Section 6.5-7%

Z->ee MC


30 Results !Results !Look at the “SIGNAL” region

AnalysisTotal

predictedbackground

Example SUSYSignal

Observed data

Trilepton (+l) 0.090.03 0.370.05 0

Trilepton(ee+l)

0.170.05 0.490.06 0

Dielectron+track

0.480.07 0.360.27 2

DY WW/ZZ WZ/* t-tbar

0.250.17

0.062 0.024

0.0320.00

5

0.0100.00

7

Details about the

dielectron + track analysis


31

Leading electrone+, pT = 41 GeV

Next-to-leadinge-, pT = 12 GeV

MET, 45 GeVIsolated track, pT = 4 GeV Muon?

Candidate event ?Candidate event ?

Mass OS1 41.6 GeV

Mass OS2 27.0 GeV

In the dielectron + track analysis, we observe one interesting event

Trileptons at DOTrileptons at DO


33 DO detectorDO detector

=1.0=0

=2.0

=3.0=1.0

=3.6

•Coverage to muons up to eta~2


34Chargino and Neutralino in Chargino and Neutralino in 33+E+ETT

In mSUGRA:3 leptons+ET

xBR~0.2 pbVery clean signature

SM background very small !

Selection SM expected OBSERVED

ee+t 0.21±0.12 0

et 0.31±0.13 0

t 1.75±0.57 2

±± 0.64±0.38 1

e+t 0.58±0.14 0

+t 0.36±0.13 1

SUM 3.85±0.75 4

M(e (GeV/c2)

6 analyses:

-2l(l=e,,)+isolated track or

ET and topological cuts (M,Δ,

MT)


35 Chargino Neutralino Chargino Neutralino

LimitsLimitsmSUGRA: M(±)≈M(02) ≈2M(01)

“3l-max”

• M( ) > M(02)• No slepton mixing

Limits : xBR < 0.2 pb M(±1)>116 GeV/c2

“Heavy Squarks”• M(±)≈M(02)3M(q)

xBR < 0.2 pb M(±1)>128 GeV/c2

“Large m0”• M()>>M(02 ,±) No sensitivity

~~

Start testing above LEP limit for mSUGRA-but LEP Model

Independent !!

A0=0

~~ ~

~

~ ~ ~

~

~ ~~

~mSugra optimis

tic scenari

o


36Summary and Outlook: Summary and Outlook:

Chargino and Neutralino in Chargino and Neutralino in mSugramSugra

TRILEPTONS SIGNAL: • CDF and D0 analysed first half of data and observed no excess :(• Set limit already beyond LEP results ! (although model dependent )• 1 fb-1 of data collected and ready to be analysed M() <170 GeV) • With 4-8 fb-1 by the end of RunII we should be sensitive to Chargino masses up to ~250 GeV and xBR ~ 0.05-0.01 pb !!

Ellis, Heinemeyer, Olive, Weiglein,

hep-ph\0411216

Favoured by EW

precision data

Charginos and Charginos and NeutralinosNeutralinosin GMSBin GMSB








/

/

/


39Motivation: Run I CDF Motivation: Run I CDF

EventEvent•Run I event:

2 e, 2 and Et=56 GeV SM expectaction: 10-6 Events

•Interpretations in GMSB: Selectron Chargino/Neutralino

•Visible in inclusive diphoton Et spectrum

•Searched by Tevatron Run II, LEP and HERA

Phys.Rev.Lett.81:1791-1796,1998


40 Chargino Neutralino in Chargino Neutralino in ++EETT

D0(CDF) Event selection:-2 photons ET -> 20(13) GeV

-ET>40(45) GeV

In GMSB: 2 photons+ET

CDF‡ and D0# combined result:m(±)>209 GeV/c2

‡Phys.Rev.D.71,3

031104(2004) #Phys. Rev. Letters 94, 041801(2005)

~

SM Expected OBSERVED

D0 3.7±0.6 2

CDF 0.3±0.1 0

Charginos and Charginos and NeutralinosNeutralinosin AMSBin AMSB








/

/

/


43 Charginos in AMSB Charginos in AMSB In the AMSB scenario (01 LSP)• ±1 is the NLSP (Next-to-Lightest-Supersymmetric Particle)• lives long enough to decay outside the detector;

•c and the BR depend almost entirely upon the mass difference ±1-01

M(

±1-> 01


44 Champs Champs CHArged Massive stable Particles:

-electrically charged-massive->speed<<c-lifetime long enough to decay

outside detectorEvent Selection:-2 muons Pt> 15 GeV, isolated-Speed significantly slower than c

No SM Background!!->from DATA

Expected OBSERVED

0.66±0.06 0

~

100 GeV Staus 100 GeV Higgsino-like

Chargino 100 GeV Gaugino-like

Chargino

~

Limits in AMSB:

champ = ±

M(±1)>174 GeV/c2

Charginos and Charginos and NeutralinosNeutralinos

in Rp violatingin Rp violating








/

/

/


47 R Parity Violation R Parity Violation

• RPV tested in Production and Decay of SUSY particles

´211

u-

d

-~

-

d-´211

u

-

+~01

~133 122

Resonant sparticle production

-> ’ijk couplingSelection:

2jets+2isolated ’s ’211

RPV decay of LSP(01) -> ijk

couplingSelection: 3 (=e,)+ET+channel dependent cuts121 ->(eeee,eee,ee+νν

122 ->(,e,ee) +νν


48 RPV Neutralino DecayRPV Neutralino Decay• Model:

R-parity conserving production => two neutralinos

R-parity violating decay into leptons

One RPV couplings non-0: 122 , 121

• Final state: 4 leptons +Et

eee, ee, e, 3rd lepton Pt>3 GeV Largest Background: bb

• Interpret: M0=250 GeV, tan=5

Obs. Exp.

eel (l=e,)

0 0.5±0.4

l (l=e,)

2 0.6+1.9-0.6

122>0121>0

m(+1) >165 GeVm(+1) >181 GeV~~


49 R Parity Violation R Parity Violation LimitsLimits

(L=154 pb-1)’211

(L=160 pb-1)122 M(0(+)1)>84(165) GeV/c2

(L=238 pb-1)121 M(0(+)1)>95(181) GeV/c2

(L=200 pb-1)133 M(0(+)1)>66(118) GeV/c2

EXP OBS

1.1±0.4 2

EXP OBS

0.6±1.9

0.5±0.4

1.0±1.4

2

0

0

All improve on Run I

tan,A0=0,


50Non-collider LSP Non-collider LSP

searchessearches

See talk from Bergstrom at SUSY05

•DAMA, CDMS, Edelweiss,.. Direct LSP detection through nuclear recoil

•Icecube: indirect search for n from LSP annhiliation in the Sun


51Chargino-Neutralino: Chargino-Neutralino:

PresentPresent• Lots of searches setting limits on 0(+) masses from different sides

mSugramSugraM(M()>118)>118

GMSBGMSBM(M()>20)>20

99

AMSBAMSBM(M()>17)>17

44

Rp

M()>181

• Getting close to the most favoured masses!

• Still 1 fb-1 to analyse ! => Observe Susy or set better limits Hints from the Tevatron will help LHC to prioritise searches


52 The most favoured masses in The most favoured masses in mSugra mSugra

hep-ph/0507283

mtop = 174.3±3.4 GeV/c2

mb(mb)MS = 4.2±0.2 GeV/c2

s(Z)MS =0.1187 ± 0.002BR(b->s) = 3.52±0.42x10-

9

DMh2 = 0.1126±0.009, Δ(g-2)/2 = 19.0 ± 8.4x10-10

Simultaneous variations of M0, M1/2,tan constraining mtop,mb s and using input measurements of b->s, (g-2),DMh2, get the most probable mSugra spectrum

What about the future ?What about the future ?


54 SUSY at the LHCSUSY at the LHC

• Ecm of 14 TeV available!!

• Between 1-2 fb-1 in the first year of data taking!

• In typical mSugra scenario, squarks and gluinos dominate => signatures with jets + MET

• Very quick discovery !

What about chargino and neutralino ? (all plots from Ian Hinchliffe, SUSY05)


55

SUSY (pb) vs sparticle mass(GeV/c2) for √s=14 TeV

Chargino and Neutralino at Chargino and Neutralino at the LHCthe LHC

• Direct production cross-sections small But could be the only way to

observe SUSY if qg are heavy ! (“focus point”)

• In other regions trileptons signal enhanced from squark-gluino cascade

~~


56 Building on leptons…Building on leptons…

•Other possibilities with lepton signatures in mSugra:Jets+MET+leptons -> mass of the sparticles in the cascade

Like-sign dileptons -> still sensitive to chargino-neutralino but also on gluino pair production ! (no jet veto)

R-parity violating scenarios


57 ConclusionsConclusions

•Chargino-neutralino are the golden discovery mode at the Tevatron in virtually all the models

•Hints from the Tevatron can give directions to the LHC

•At the LHC, chargino-neutralino production crucial in study the properties of the new sparticles as their masses (but only mSugra considered)

•Exciting times to come !!


58 Back-up slidesBack-up slides


59

CDMWMAP SN IaJ. Tonry et al

D.N. Spergel et al., Astrophys.J.Suppl.148:213,2003

h2=0.12

SDSS (and 2dFGRS), 2005

Evidence for Cold Dark Matter existance

U. Seljak & al astro-ph/0407372


60 Cold Dark Matter Cold Dark Matter from from Bergstrom(SUSY05)Bergstrom(SUSY05)

• Part of the “Concordance Model”, CDM

• Gives excellent description of CMB, large scale structure, Ly-forest, gravitational lensing, supernova distances …

• If consisting of particles, may be related to electroweak mass scale: weak cross section, non-dissipative Weakly Interacting Massive Particles (WIMPs). Potentially detectable, directly or indirectly.

• May or may not describe small-scale structure in galaxies: Controversial issue, but alternatives (self-interacting DM, warm DM, self-annihilating DM) seem worse. Probably non-linear astrophysical feedback processes are acting (bar formation, tidal effects, mergers, supernova winds, …). This is a crucial problem of great importance for dark matter detection rates.

SUSY


61Good particle physics candidates for Cold Dark

Matter:Independent motivation from particle physics

• Axions (introduced to solve strong CP problem)• Weakly Interacting Massive Particles (WIMPs, 3 GeV < mX < 50 TeV), thermal relics from Big Bang: Supersymmetric neutralino

Axino, gravitinoKaluza-Klein statesHeavy neutrino-like particles

Mirror particles”Little Higgs”plus hundreds more in literature…

• Non-thermal (maybe superheavy) relics:wimpzillas, cryptons, …

”The WIMP miracle”: for typical gauge couplings and masses of order the electroweak scale, wimph2 0.1 (within factor of 10 or so)

from Bergstrom(SUSY05)from Bergstrom(SUSY05)


62 More on More on Dark MatterDark Matter• From the WMAP results,

in mSugra there are only 4 regions allowed

• Too much DM unless LSP light Annihilation enhanced

Degeneracy or LSP content

• But: If (g-2) is due to SUSY,

the sparticles masses are small ~102 GeV M1/2

M0

However, general MSSM model versions give more freedom. At least 3 additional parameters: , At, Ab (and perhaps several more…)

In particular: special models like split supersymmetry, models with CP violation, etc.


63Current constrained Current constrained

regionsregions

a in [10;40]10-10

Higgs mass < 114.1 GeV Collider physics

direct searches for sparticles

Higgs bound

Astrophysics

cold dark matter

Low energy

a

b into s


64 Teavatron reach in MTeavatron reach in M00-M-M1212


65Indirect constraints on mSugra: Indirect constraints on mSugra:

BBss

• SM rate heavily suppressed:

• SUSY rate may be enhanced:

€

BR(Bs → μ +μ−) = (3.5 ± 0.9) ×10−9

(Buchalla & Buras, Misiak & Urban)

S. Baek, Y.G.Kim, P. Ko, hep-ph/0406033

Complementary to

trilepton searches


68Impact of BImpact of Bss Limits: Limits:

Now Now S. Baek, Y.G.Kim, P. Ko, hep-ph/0406033 R. Dermisek, S. Raby, L. Roszkowski,

R. Ruiz de Austri, hep-ph/0507233


69Impact of BImpact of Bss Limits: L=8 Limits: L=8 fbfb-1-1

• Will severely constrain parameter space “Tevatron can rule out 29% of parameter space allowed by WMAP

data within mSUGRA.” B. Allanach, C. Lester, hep-ph/0507283

R. Dermisek, S. Raby, L. Roszkowski, R. Ruiz de Austri, hep-ph/0507233

S. Baek, Y.G.Kim, P. Ko, hep-ph/0406033


70 JES ScaleJES Scale


71Chargino-Neutralino Chargino-Neutralino

masses(mSugra)masses(mSugra)

Little dependence on M0, high on M1/2

M(±) (GeV/c2)

M(02)

(GeV/c2)


72 Other massesOther masses

M(chargino)M(slepton)

BR(leptons) enhanced

M(eR) (GeV/c2)

M(eR)-M(±) (GeV/c2)


73 Trileptons at D0Trileptons at D0

Selection Main BG Main Systematic

ee+l Zgg,Wenu JES,MC stat

e+l QCD(38%) Wenu,WW,WZ JES(3%),QCD,eff

+l WZ,Wmunu QCD,JES,reco

SUM QCD(m),WZ(e) JES,modelling of qcd bg


74 Chargino Neutralino in Chargino Neutralino in ++EETT

D0(CDF) Event selection:-2 photons ET > 20(13) GeV

-ET>40(45) GeV

In GMSB: 2 photons+ET

Limit Main Syst Main BG

D0 195 GeV gID (8%) QCD (70%)

CDF 167 GeV gID (14%) eg(50%)

CDF‡ and D0# combined result:m(±)>209 GeV/c2

‡Phys.Rev.D.71,3

031104(2004) #Phys. Rev. Letters 94, 041801(2005)


75 Tau identificationTau identification

- narrow- narrow cluster in central calorimetercluster in central calorimeter-search for matching high-Pt track-search for matching high-Pt track

-define 2 cones 10-define 2 cones 10oo and 30 and 30o o around the trackaround the track-let more tracks to enter in the inner cone-let more tracks to enter in the inner cone

---discard event if there are tracks between the -discard event if there are tracks between the

2 cones2 cones-reconstruct the cluster in the ShowerMax and -reconstruct the cluster in the ShowerMax and

create a create a 00

-select events with mass(-select events with mass(00 ,tracks) < M(tau) ,tracks) < M(tau)

-check E(cal) = sum(P)(tracks+ -check E(cal) = sum(P)(tracks+ 00))


76 Susy at the LHC !Susy at the LHC !

• Will generally be found fast!

• But SUSY comes in very many flavours

• Hints from the Tevatron would help on search priorities, e.g. tan large:

3rd generation important (’s, b’s)

R-parity is violated No ET

GMSB models: Photons important

Split-SUSY: Stable charged hadrons

Can setup triggers accordingly


77 Mass measurements at the Mass measurements at the LHCLHC

Ian Hinchliffe, SUSY05)


78 ……continue…continue…Ian Hinchliffe, SUSY05)


79 ……continuecontinue Ian Hinchliffe, SUSY05)

searches for supersymmetry at the tevatron

Documents

susy particlessupersymmetry

m12stau coannihilation

mstaufunnel region ma

gevc2 rp conserving

sm particles

striking signaturesin

main regions

ew radiative corrections