Supersymmetry at D Supersymmetry at D Ø Ø and other new phenomena searches in and other new phenomena searches in Run II Run II – TeVatron and D TeVatron and D Ø Ø upgrade upgrade – Run II preliminary studies Run II preliminary studies • mSUGRA : squarks and gluinos jet + mET mSUGRA : squarks and gluinos jet + mET • GMSB : diphotons GMSB : diphotons • RPV : trileptons / likesign dileptons RPV : trileptons / likesign dileptons • Extra-dimensions Extra-dimensions Auguste BESSON for the D0 collaboration Auguste BESSON for the D0 collaboration PASCOS 2003 PASCOS 2003
PASCOS 2003. Supersymmetry at D Ø. and other new phenomena searches in Run II TeVatron and D Ø upgrade Run II preliminary studies mSUGRA : squarks and gluinos jet + mET GMSB : diphotons RPV : trileptons / likesign dileptons Extra-dimensions. Auguste BESSON for the D0 collaboration. - PowerPoint PPT Presentation
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Supersymmetry at DSupersymmetry at DØØSupersymmetry at DSupersymmetry at DØØ
and other new phenomena searches in and other new phenomena searches in Run IIRun II
– TeVatron and DTeVatron and DØØ upgrade upgrade– Run II preliminary studiesRun II preliminary studies
• p-pbar colliderp-pbar collider• Run IIa : Run IIa : march 2001march 2001• Energy: Energy: 1.8 1.8 1.96 TeV 1.96 TeV
• LuminosityLuminosity– new injector : new injector : main injectormain injector– # bunches : # bunches : 6 x 6 6 x 6 → → 336 x 366 x 36– pbar production pbar production – pbar recycling : pbar recycling :
Recycler Recycler (Run IIb)(Run IIb)
FermilaFermilabb
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 3
TeVatron upgrade TeVatron upgrade (2)(2)TeVatron upgrade TeVatron upgrade (2)(2)Run 1bRun 1b Run 2aRun 2a Run 2 Run 2
squark masssquark mass (GeV)(GeV) mm0 0 (GeV)(GeV)
mm1
/2
1/2
(G
eV
)(G
eV
)
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 12
squarks and gluinossquarks and gluinossquarks and gluinossquarks and gluinos
• Final StateFinal State>=2 jets + mET>=2 jets + mET
PRL 83, 4937 (1999)
no E
WSB
Run IRun IRun IRun I
tan tan = 2; = 2; < 0; A < 0; A00 = 0 = 0
D0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminary
2 jets2 jetsmETmET
D0 Run II preliminaryD0 Run II preliminary
(jet1-jet2)(jet1-jet2)
- MC. Data
L ~ 6 pbL ~ 6 pb-1-1
significant cuts:mET, pTjets scalar sum of ETacoplanarity
GMSBGMSBGMSBGMSB
frameworkframeworkRun II preliminary study: Run II preliminary study: di-photons + di-photons +
mETmET
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 14
GMSBGMSBGMSBGMSB• Minimal Model of Gauge Mediation (MGM) Minimal Model of Gauge Mediation (MGM)
6 parameters :6 parameters : effective visible sector SUSY breaking parametereffective visible sector SUSY breaking parameterNN number of messengernumber of messengerMMmm mass scale of messengersmass scale of messengerstan tan ratio of v.e.v. of the 2 higgs doubletsratio of v.e.v. of the 2 higgs doubletssign(sign()) sign of mixing parameter of higgsinossign of mixing parameter of higgsinosCCGG ratio of the messenger sector SUSY breaking ratio of the messenger sector SUSY breaking order parameter to the intrinsic SUSY breaking order parameter to the intrinsic SUSY breaking parameterparameter
– NLSP nature. either: NLSP nature. either:
0011, stau, slepton, squark, etc., stau, slepton, squark, etc.– lifetime of NLSPlifetime of NLSP– signature:signature:
+mET; l+mET; lll+mET ; +mET ; +mET,+mET,
monojetmonojet
Fermilab Run II workshop:Baer et al. hep-ph/0008070Baer et al. hep-ph/9903333
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 15
• Neutralino NLSPNeutralino NLSP
• Final state:Final state: + mET + X+ mET + X
N = 1; MN = 1; Mmm = 2 = 2 ;; tan tan =15; =15; > 0 > 0
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 18
• R-p conserved:R-p conserved:- LSP stable and candidate for dark matter LSP stable and candidate for dark matter - Susy particles pair producedSusy particles pair produced
• R-p violated:R-p violated: B or L not conserved B or L not conserved
• Lightest Susy Particle (LSP) decays eitherLightest Susy Particle (LSP) decays either- inside the detector - inside the detector (with or without a displaced vertex)(with or without a displaced vertex)
- outside the detectoroutside the detector • Susy signature can be very differentSusy signature can be very different
– Less missing EtLess missing Et– More leptons More leptons (( or or ’)’) and jets and jets ((’ or ’ or ’’)’’)
• Single Susy particle production is possibleSingle Susy particle production is possible- via via ’ or ’ or ’’ @ TeVatron’’ @ TeVatron- cross-section cross-section ( (’’ijkijk))22
misidentification of jets as electrons, cosmic misidentification of jets as electrons, cosmic
Final State : Final State : eee,ee eee,ee,e,e,, + missing ET + missing ETFinal State : Final State : eee,ee eee,ee,e,e,, + missing ET + missing ET
e01
~e
~
e121
e e ee e e
SM backgdSM backgd 0.9 0.9 0.20.2
InstrumentalInstrumental 1 1 0.3 0.3
DataData 22
e e e e
SM backgdSM backgd 0.13 0.13 0.08 0.08
e + e + + e fake + e fake 0.6 0.6 0.2 0.2
e + e + cosmic e + e + cosmic
0.145 0.145 0.0140.014
DataData 11
D0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminary
L = 5.2 L = 5.2 0.8 pb0.8 pb-1-1
Large Extra DimensionsLarge Extra DimensionsLarge Extra DimensionsLarge Extra Dimensions
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 23
Large extra dimensionsLarge extra dimensionsLarge extra dimensionsLarge extra dimensions• Virtual gravitonVirtual graviton
– Planck scale MsPlanck scale Ms
• final statefinal state ee, ee, , ,
Instrumental- Inst. + S.M. backgd
+ Data
Run I Limit: (95% C.L.)Run I Limit: (95% C.L.)Ms(GRW) > 1.2 TeVMs(GRW) > 1.2 TeVRun II preliminary:Run II preliminary:Ms(GRW) > 0.92 TeVMs(GRW) > 0.92 TeV
L = 9.9 pbL = 9.9 pb-1-1L = 9.9 pbL = 9.9 pb-1-1
diEM Mass (GeV)diEM Mass (GeV)
cos
cos
**
S.M.S.M.S.M.S.M. DataDataDataData
E.D. E.D. signalsignalE.D. E.D. signalsignal
QCDQCDQCDQCD
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 24
D0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminary
ETET11(GeV)(GeV) ETET22 11 22 cos cos ** MM mETmET
120.3120.3 106.106.22
0.100.10 -2.10-2.10 0.770.77 377377 12.612.6
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 25
ConclusionConclusionConclusionConclusion• D0 detector: D0 detector: upgrade is a successupgrade is a success
tremendous effort on calibration, tremendous effort on calibration, comissioning,comissioning,
instrumental backgd, particle ID, etc.instrumental backgd, particle ID, etc.
• first new phenomena analysis underwayfirst new phenomena analysis underway– many exciting channelsmany exciting channels
• Luminosity Luminosity large progress during the last monthslarge progress during the last months
– now: ~ 50 pbnow: ~ 50 pb-1-1 on tape on tape– ~ 200 pb~ 200 pb-1-1 in summer 2003 in summer 2003– First Run II limits in the coming months.First Run II limits in the coming months.
(better than the Run I results)(better than the Run I results)Stay tuned !Stay tuned !
Back upBack upBack upBack up
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 27
• SUSY SUSY - New symmetry between fermions and - New symmetry between fermions and bosonsbosons- Solves hierarchy problem- Solves hierarchy problem- allows convergence of coupling - allows convergence of coupling constants at GUT scaleconstants at GUT scale- complete new spectrum of susy - complete new spectrum of susy particlesparticles..
• In most of the modelsIn most of the models- SUSY particles are pair produced- SUSY particles are pair produced
- The lightest SUSY particle (LSP) is - The lightest SUSY particle (LSP) is stable and escape from detector.stable and escape from detector.
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 33
MEMETT =31.8 GeV =31.8 GeV
mm = 41.5 GeV/c = 41.5 GeV/c22
2211ee
ppTT = = 9.9.82 82 GeVGeV
= = -1.48-1.48
= = 2.882.88
Charge = 1Charge = 1
ppTT = = 228.2 8.2 GeVGeV
= = -0.-0.1010
= = 6.206.20
Charge = -1Charge = -1
EETT = = 19.2 GeV19.2 GeV
= 0.40= 0.40
= 0.63= 0.63
No track No track matchmatch
Muon
Electron
MET
Muon system
Muon
ee candidate event candidate eventee candidate event candidate eventD Run 2 PreliminaryD0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminary
PASCOS 2003. 3-8 January 2003 Auguste Besson for D0 collab. 34
eeee candidate event candidate eventeeee candidate event candidate eventD0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminaryD0 Run II preliminary