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Searches for Supersymmetry at the Tevatron. Liverpool HEP Seminar Thursday 15th December 2005. Giulia Manca, University of Liverpool. “Supersymmetry”, by Karl Hager From the artist’s website http://www.cassetteradio.com/cubagallery/hagen.htm

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Searches for supersymmetry at the tevatron

Searches for Supersymmetry at the Tevatron

Liverpool HEP Seminar

Thursday 15th December 2005

Giulia Manca, University of Liverpool


Searches for supersymmetry at the tevatron

“Supersymmetry”, by Karl Hager

From the artist’s website

http://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


Outline

Outline

  • Supersymmetry

  • The Tevatron and its experiments

  • Searching for Chargino

    and Neutralino

  • Conclusions

  • Outlook

Giulia Manca, University of Liverpool


Supersymmetry introduction

Supersymmetry: Introduction

~

f

f

H

H

H

H

~

f

f

  • 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!

Giulia Manca, University of Liverpool


Supersymmetry models

Supersymmetry: models

Determines the SUSY Mass spectrum!

  • Different mechanisms of susy breaking lead to different models

Giulia Manca, University of Liverpool


Supersymmetry particles

Supersymmetry: particles

g

~

G

ci

4 neutralinos

2 charginos

G

c0i

1. mSugra and AMSB: c01LSP, stable

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

~

2. GMSB: G LSP,stable

+1 (SM particles)

R-Parity Quantum Number->

-1 (Susy particles)

Giulia Manca, University of Liverpool


Supersymmetry why

Supersymmetry: why ?

  • Solves “Hierarchy Problem”

  • ProvidesGrand Unification Theoryat the 1016 GeV scale

  • Consistent with results fromPrecision Datafits

  • Rp Conserving models providegoodDark Matter Candidate(LSP)

New Top Mass

172.7 GeV/c2

Giulia Manca, University of Liverpool


Supersymmetry dark matter

Supersymmetry & Dark Matter

  • 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

M1/2

(GeV)

  • bulk region (low m0 and m1/2)

  • stau coannihilation region m  mstau

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

  • funnel region (mA,H 2m)

M0(GeV)

Giulia Manca, University of Liverpool


Supersymmetry dark matter1

Supersymmetry & Dark Matter

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

H. Baer, A. Belyaev, T. Krupovnickas, J. O’Farrill, JCAP 0408:005,2004

M1/2

  • bulk region (low m0 and m1/2)

  • stau coannihilation region m  mstau

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

  • funnel region (mA,H 2m)

M0

Giulia Manca, University of Liverpool


Supersymmetry how

Supersymmetry: how ?

Rp :

LSP

:

c c±

(fb)

GMSB:

2 LSPs

1012

Remember :

VERY SMALL cross sections !!

104

10

Wide range of signatures: look for SuSy specific signatures or

excess in SM ones; examples:

  • Large Missing Energy ET

  • Isolated leptons

  • Multijets

  • Diphotons

Giulia Manca, University of Liverpool


The tevatron

The Tevatron

design goal

Still long way to go!

p p at ECM 1.96 TeV

base goal

  • High Luminosity

    • Tevatron 1 fb-1!

  • CDF and D0 running at high efficiency

Mar01-Jul04

350pb-1

Giulia Manca, University of Liverpool


Charginos and neutralinos

Charginos and Neutralinos


Why charginos and neutralinos

Why Charginos and Neutralinos ?

  • They are light(~ 100-500 GeV/c2)

    • Squarks and gluinos too heavy for the Tevatron

  • They decay giving striking signatures

    • In mSugra : 3 isolated leptons + ET

    • In GMSB : 2 photons + ET

    • In AMSB : long-lived particles

    • In Rp models : >3 leptons

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

/

/

/

Giulia Manca, University of Liverpool


The trilepton signal

The trilepton signal

CHARGINOS NEUTRALINOS

Higgsinos and gauginos mix

Striking signature at Hadron Collider,

THREE LEPTONS

In mSUGRA Rp conserved scenario,

LARGE MISSING TRANSVERSE ENERGY from the stable LSP+

  • Low background

  • Easy to trigger

    LOW MODEL DEPENDENCE

GOLDEN SIGNAL AT THE TEVATRON !!

Giulia Manca, University of Liverpool


Existing limits lep

Existing Limits : LEP

SM Higgs Limits

Slepton Limits

Chargino-Limits

LEP I Precision measurements

Theoretically forbidden

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

Giulia Manca, University of Liverpool


Adlo exclusion plots

ADLO exclusion plots

Giulia Manca, University of Liverpool


Chargino neutralino production

Chargino-Neutralino production…

T. Plehn, PROSPINO

SUSY (pb) vs sparticle mass(GeV/c2) for √s=1.96 TeV

W*

10

1

c c±

10-1

10-2

10-3

100 150 200 250 300 350 400 450 500

  • Low cross section

    (weakly produced)

t-channel interferes destructively

Tevatron sensitive to the BULK region in WMAP data

Giulia Manca, University of Liverpool


And decay

…and decay

Z*

W*

Leptons of 3rd generation

are preferred

Leptons of 1st, 2nd generation

are preferred

Chargino Decay

Neutralino Decay

Best reach for the Tevatron

for mass sleptons~mass chargino

=> BR (3l) enhanced

Giulia Manca, University of Liverpool


Trileptons at cdf

Trileptons at CDF


How to investigate the different scenarios

How to investigate the different scenarios?

Acceptance

improvement

Low tan scenario tan=5 , 38%

High tan scenario tan=20, 100%

sensitive

to leptonic  decay

Low tan

region

High tan

region

sensitive

to hadronic  decay

High pT data-sample benchmark

to understand low pT data-sample

Giulia Manca, University of Liverpool


Event kinematic

Event kinematic

Leading lepton

Next-To-Leading lepton

Third lepton

Chargino and Neutralino

prompt decay

Lepton pT (GeV)

Typical SUSY leptons

Leptons

separated in space

EWK range

Lepton pT thresholds

  • trilepton analyses 20,8,5 GeV

  • dielectron + track analysis 10,5,4 GeV

Giulia Manca, University of Liverpool


Finding susy at cdf

Finding SUSY at CDF

=0

e

=1

Muon system

Recover loss in acceptance due to cracks in the detector if we accept muons with no hits in the Muon Chamber

Missing Transverse Energy

(MET)

Drift chamber

Em Calorimeter

Had Calorimeter

CENTRAL REGION

Real MET

  • Particles escaping detection ()

    Fake MET

    • Muon pT or jet ET mismeasurement

    • Additional interactions

    • Cosmic ray muons

    • Mismeasurement of the vertex

Giulia Manca, University of Liverpool


Backgrounds

Backgrounds

e

e

e

0

The third lepton is a fake lepton



Backgrounds

  • DIBOSON (WZ,ZZ) PRODUCTION

  • Leptons have high pT

  • Leptons are isolated and separated

  • MET due to neutrinos

    irreducible background

  • DRELL YAN PRODUCTION + additional lepton

  • Leptons have mainly high pT

  • Small MET

  • Low jet activity

HEAVY FLAVOUR PRODUCTION

  • Leptons mainly have low pT

  • Leptons are not isolated

  • MET due to neutrinos

The third lepton originates from  conversion

e

e

Giulia Manca, University of Liverpool


Searches for supersymmetry at the tevatron

Analysis Strategy

COUNTING EXPERIMENT

  • Optimiseselection criteria for best signal/background value;

  • Apply selection criteria to the data

  • Definethe 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

Giulia Manca, University of Liverpool


Selection criteria i mass

Selection criteria: (I) Mass

# dimuon pairs

Rejection of J/,  and Z

Dimuon events

  • Mll<76 GeV & Mll>106 GeV

  • Mll> 15 GeV

  • min Mll< 60 GeV

    (dielectron+track analysis)

Giulia Manca, University of Liverpool


Ii deltaphi l l jet veto

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

Rejection of DY and high jet multiplicity processes

Giulia Manca, University of Liverpool


Iii met selection

(III) MET selection

Further reducing DY by MET > 15 GeV

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

…Still BLIND !

Giulia Manca, University of Liverpool


Understanding of the data

Understanding of the Data

??

MET

Diboson

10 15

DY + 

Z + fake

15 76 106

Invariant Mass

  • Each 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)

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

SIGNAL REGION

Very good agreement between

SM prediction and observed data

Giulia Manca, University of Liverpool


Systematic uncertainty

Systematic 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

Giulia Manca, University of Liverpool


Results

Results !

Look at the “SIGNAL” region

Details about the

dielectron + track analysis

Giulia Manca, University of Liverpool


Candidate event

Candidate event ?

Next-to-leading

e-, pT = 12 GeV

Leading electron

e+, pT = 41 GeV

Isolated track, pT = 4 GeV

Muon?

MET, 45 GeV

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

Giulia Manca, University of Liverpool


Trileptons at do

Trileptons at DO


Do detector

DO detector

=1.0

=0

=1.0

=2.0

=3.0

=3.6

  • Coverage to muons up to eta~2

Giulia Manca, University of Liverpool


Chargino and neutralino in 3 e t

Chargino and Neutralino in 3+ET

  • sxBR~0.2 pb

  • Very clean signature

  • SM background very small !

InmSUGRA:3leptons+ET

6 analyses:

-2l(l=e,m,t)+isolated track or mm

- ET and topological cuts (M,Df, MT)

M(et) (GeV/c2)

Giulia Manca, University of Liverpool


Chargino neutralino limits

Chargino Neutralino Limits

~

~

~

mSUGRA:M(c±)≈M(c02)≈2M(c01)

“3l-max”

  • M()>M(c02)

  • Nosleptonmixing

    Limits:

  • sxBR<0.2pb

  • M(c±1)>116GeV/c2

    “HeavySquarks”

    • M(c±)≈M(c02)3M(q)

  • sxBR<0.2pb

  • M(c±1)>128GeV/c2

    “Largem0”

    • M()>>M(c02,c±)

    • Nosensitivity

  • ~

    ~

    mSugra optimistic scenario

    A0=0

    ~

    ~

    ~

    ~

    ~

    ~

    ~

    ~

    ~

    Start testing above LEP limit for mSUGRA-but LEP Model Independent !!

    Giulia Manca, University of Liverpool


    Summary and outlook chargino and neutralino in msugra

    Summary and Outlook: Chargino and Neutralino in mSugra

    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 andsxBR~ 0.05-0.01 pb !!

    Ellis, Heinemeyer, Olive, Weiglein,

    hep-ph\0411216

    Favoured by EW precision data

    Giulia Manca, University of Liverpool


    Charginos and neutralinos in gmsb

    Charginos and Neutralinosin GMSB


    Why charginos and neutralinos1

    Why Charginos and Neutralinos ?

    • They are light(~ 100-500 GeV/c2)

      • Squarks and gluinos too heavy for the Tevatron

    • They decay giving striking signatures

      • In mSugra : 3 isolated leptons + ET

      • In GMSB : 2 photons + ET

      • In AMSB : long-lived particles

      • In Rp models : >3 leptons

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

    /

    /

    /

    Giulia Manca, University of Liverpool


    Motivation run i cdf event

    Motivation: Run I CDF Event

    • Run I event:

      • 2 e, 2 g 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

    Giulia Manca, University of Liverpool


    Chargino neutralino in gg e t

    Chargino Neutralino in gg+ET

    ~

    In GMSB: 2 photons+ET

    D0(CDF)Eventselection:

    -2photonsET->20(13)GeV

    -ET>40(45)GeV

    CDF‡ and D0# combined result:

    m(c±)>209 GeV/c2

    ‡Phys.Rev.D.71,3 031104(2004)

    #Phys. Rev. Letters 94,

    041801(2005)

    Giulia Manca, University of Liverpool


    Charginos and neutralinos in amsb

    Charginos and Neutralinosin AMSB


    Why charginos and neutralinos2

    Why Charginos and Neutralinos ?

    • They are light(~ 100-500 GeV/c2)

      • Squarks and gluinos too heavy for the Tevatron

    • They decay giving striking signatures

      • In mSugra : 3 isolated leptons + ET

      • In GMSB : 2 photons + ET

      • In AMSB : long-lived particles

      • In Rp models : >3 leptons

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

    /

    /

    /

    Giulia Manca, University of Liverpool


    Charginos in amsb

    Charginos in AMSB

    • In the AMSB scenario (c01 LSP)

    • c±1is 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 c±1-c01

    • c±1-> c01

    M(

    Giulia Manca, University of Liverpool


    Champs

    Champs

    100 GeV Staus

    100 GeV Higgsino-like

    Chargino

    100 GeV Gaugino-like

    Chargino

    CHArged Massive stable Particles:

    -electrically charged

    -massive->speed<<c

    -lifetime long enough to decay

    outside detector

    Event Selection:

    -2 muons Pt> 15 GeV, isolated

    -Speed significantly slower than c

    No SM Background!!->from DATA

    Limits in AMSB:

    champ = c ±1

    • M(c±1)>174 GeV/c2

    ~

    ~

    Giulia Manca, University of Liverpool


    Charginos and neutralinos in rp violating

    Charginos and Neutralinosin Rp violating


    Why charginos and neutralinos3

    Why Charginos and Neutralinos ?

    • They are light(~ 100-500 GeV/c2)

      • Squarks and gluinos too heavy for the Tevatron

    • They decay giving striking signatures

      • In mSugra : 3 isolated leptons + ET

      • In GMSB : 2 photons + ET

      • In AMSB : long-lived particles

      • In Rp models : >3 leptons

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

    /

    /

    /

    Giulia Manca, University of Liverpool


    R parity violation

    R Parity Violation

    -

    d

    -

    d

    ~

    0

    1

    ~

    ´211

    +

    ´211

    ~

    u

    -

    -

    -

    u

    • RPVtestedinProductionandDecayofSUSYparticles

    l133

    l122

    m+

    m-

    • Resonant sparticle production

      -> l’ijk coupling

    • Selection:

      2jets+2isolated m’s

      • l’211

    • RPV decay of LSP(c01) -> lijk coupling

    • Selection:

    • 3 (=e,m)+ET+channel dependent cuts

    • l121 ->(eeee,eeem,eemm) +nn

    • l122 ->(mmmm,mmme,mmee) +nn

    Giulia Manca, University of Liverpool


    Rpv neutralino decay

    RPV Neutralino Decay

    • Model:

      • R-parity conserving production => two neutralinos

      • R-parity violating decay into leptons

      • One RPV couplings non-0: l122 , l121

    • Final state: 4 leptons +Et

      • eee, eem, mme, mmm

      • 3rd lepton Pt>3 GeV

      • Largest Background: bb

    • Interpret:

      • M0=250 GeV, tanb=5

    l121>0

    l122>0

    ~

    ~

    m(c+1) >165 GeV

    m(c+1) >181 GeV

    Giulia Manca, University of Liverpool


    R parity violation limits

    R Parity Violation Limits

    • (L=154 pb-1) : l’211

    • (L=160 pb-1) : l122 M(c0(+)1)>84(165) GeV/c2

    • (L=238 pb-1) : l121M(c0(+)1)>95(181) GeV/c2

    • (L=200 pb-1) : l133M(c0(+)1)>66(118) GeV/c2

    tanb=2,A0=0,m<0

    All improve on Run I

    Giulia Manca, University of Liverpool


    Non collider lsp searches

    Non-collider LSP searches

    • DAMA, CDMS, Edelweiss,..

      • Direct LSP detection through nuclear recoil

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

    See talk from Bergstrom at SUSY05

    Giulia Manca, University of Liverpool


    Chargino neutralino present

    Chargino-Neutralino: Present

    • Lots of searches setting limits on c0(+) masses from different sides

    c c±

    Rp

    M(c±)>181

    mSugra

    M(c±)>118

    AMSB

    M(c±)>174

    GMSB

    M(c±)>209

    • 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

    Giulia Manca, University of Liverpool


    The most favoured masses in msugra

    The most favoured masses in mSugra

    hep-ph/0507283

    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

    mtop = 174.3±3.4 GeV/c2

    mb(mb)MS = 4.2±0.2 GeV/c2

    s(Z)MS =0.1187 ± 0.002

    BR(b->s) = 3.52±0.42x10-9

    DMh2 = 0.1126±0.009,

    (g-2)/2 = 19.0 ± 8.4x10-10

    Giulia Manca, University of Liverpool


    What about the future

    What about the future ?


    Susy at the lhc

    SUSY 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)

    Giulia Manca, University of Liverpool


    Chargino and neutralino at the lhc

    Chargino and Neutralino at the LHC

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

    • Directproductioncross-sectionssmall

      • ButcouldbetheonlywaytoobserveSUSYifqgareheavy!(“focuspoint”)

    • Inotherregionstrileptonssignalenhancedfromsquark-gluinocascade

    ~

    ~

    Giulia Manca, University of Liverpool


    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

    Giulia Manca, University of Liverpool


    Conclusions

    Conclusions

    • 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 !!

    Giulia Manca, University of Liverpool


    Back up slides

    Back-up slides

    Giulia Manca, University of Liverpool


    Searches for supersymmetry at the tevatron

    Evidence for Cold Dark Matter existance

    SN Ia

    WMAP

    J. Tonry et al

    LCDM

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

    U. Seljak & al astro-ph/0407372

    WMh2=0.12

    SDSS (and 2dFGRS), 2005

    Giulia Manca, University of Liverpool


    Cold dark matter from bergstrom susy05

    Cold Dark Matter from Bergstrom(SUSY05)

    • Partofthe “ConcordanceModel”,WCDM  0.3, WL  0.7

    • GivesexcellentdescriptionofCMB,largescalestructure,Ly-aforest,gravitationallensing,supernovadistances …

    • Ifconsistingofparticles,mayberelatedtoelectroweakmassscale:weakcrosssection,non-dissipativeWeaklyInteractingMassiveParticles(WIMPs).Potentiallydetectable,directlyorindirectly.

    • Mayormaynotdescribesmall-scalestructureingalaxies:Controversialissue,butalternatives(self-interactingDM,warmDM,self-annihilatingDM)seemworse.Probablynon-linearastrophysicalfeedbackprocessesareacting(barformation,tidaleffects,mergers,supernovawinds, …).Thisisacrucialproblemofgreatimportancefordarkmatterdetectionrates.

    SUSY

    Giulia Manca, University of Liverpool


    Searches for supersymmetry at the tevatron

    from Bergstrom(SUSY05)

    Good 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, gravitino

    Kaluza-Klein states

    Heavy 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, Wwimph2 0.1 (within factor of 10 or so)

    Giulia Manca, University of Liverpool


    More on dark matter

    More on Dark Matter

    • FromtheWMAPresults,

      inmSugrathereareonly4regionsallowed

    • ToomuchDMunless

      • LSPlight

      • Annihilationenhanced

        • DegeneracyorLSPcontent

    • But:

      • If(g-2)isduetoSUSY,

        thesparticlesmassesare

        small~102GeV

    M1/2

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

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

    M0

    Giulia Manca, University of Liverpool


    Current constrained regions

    Current constrained regions

    Higgs mass < 114.1 GeV

    • Collider physics

      • direct searches for sparticles

      • Higgs bound

    • Astrophysics

      • cold dark matter

    • Low energy

      • a

      • b into s

    a in [10;40]10-10

    Giulia Manca, University of Liverpool


    Teavatron reach in m 0 m 12

    Teavatron reach in M0-M12

    Giulia Manca, University of Liverpool


    Indirect constraints on msugra b s m m

    Indirect constraints on mSugra: Bsm+m-

    • SM rate heavily suppressed:

    • SUSY rate may be enhanced:

    (Buchalla & Buras, Misiak & Urban)

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

    Complementary to trilepton searches

    Giulia Manca, University of Liverpool


    Impact of b s m m limits now

    Impact of Bsm+m- Limits: Now

    R. Dermisek, S. Raby, L. Roszkowski,

    R. Ruiz de Austri, hep-ph/0507233

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

    Giulia Manca, University of Liverpool


    Impact of b s m m limits l 8 fb 1

    Impact of Bsm+m- Limits: L=8 fb-1

    R. Dermisek, S. Raby, L. Roszkowski,

    R. Ruiz de Austri, hep-ph/0507233

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

    • 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

    Giulia Manca, University of Liverpool


    Jes scale

    JES Scale

    Giulia Manca, University of Liverpool


    Chargino neutralino masses msugra

    Chargino-Neutralino masses(mSugra)

    M(±) (GeV/c2)

    M(02) (GeV/c2)

    Little dependence on M0, high on M1/2

    Giulia Manca, University of Liverpool


    Other masses

    Other masses

    M(eR) (GeV/c2)

    M(chargino)M(slepton)

    BR(leptons) enhanced

    M(eR)-M(±) (GeV/c2)

    Giulia Manca, University of Liverpool


    Trileptons at d0

    Trileptons at D0

    Giulia Manca, University of Liverpool


    Chargino neutralino in gg e t1

    Chargino Neutralino in gg+ET

    In GMSB: 2 photons+ET

    D0(CDF)Eventselection:

    -2photonsET>20(13)GeV

    -ET>40(45)GeV

    CDF‡ and D0# combined result:

    m(c±)>209 GeV/c2

    ‡Phys.Rev.D.71,3 031104(2004)

    #Phys. Rev. Letters 94,

    041801(2005)

    Giulia Manca, University of Liverpool


    Tau identification

    Tau identification

    - narrowcluster in central calorimeter

    -search for matching high-Pt track

    -define 2 cones 10o and 30o around the track

    -let more tracks to enter in the inner cone

    --discard event if there are tracks between the

    2 cones

    -reconstruct the cluster in the ShowerMax and

    create a p0

    -select events with mass(p0 ,tracks) < M(tau)

    -check E(cal) = sum(P)(tracks+ p0)

    Giulia Manca, University of Liverpool


    Susy at the lhc1

    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.

      • tanb large:

        • 3rd generation important

          (t’s, b’s)

      • R-parity is violated

        • No ET

      • GMSB models:

        • Photons important

      • Split-SUSY:

        • Stable charged hadrons

      • Can setup triggers accordingly

    Giulia Manca, University of Liverpool


    Mass measurements at the lhc

    Mass measurements at the LHC

    Ian Hinchliffe, SUSY05)

    Giulia Manca, University of Liverpool


    Continue

    …continue…

    Ian Hinchliffe, SUSY05)

    Giulia Manca, University of Liverpool


    Continue1

    …continue

    Ian Hinchliffe, SUSY05)

    Giulia Manca, University of Liverpool


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