R-parity violating Supersymmetry III Phys. Inst. A, RWTH Aachen Introduction to R-parity violating SUSY Three DØ searches via non-zero LLE (short and long lived LSP) and LQD couplings Perspectives for at the LHC
R-Parity Violation Supersymmetry R -parity: W W R/ P = W MSSM R P + W = ( ) R/ P 3B+ L+ 2S ' '' = λ L L E + λ LQ D + λ U ijk i j k ijk i j k ijk i 2 S is the particle spin, B is the baryon number, L is the lepton number D D j k R-parity violating extension of the MSSM i,j,k =,2,3 generation indices 2 R-parity conserving production associated/pair production of gauginos decay via λ ijk into 4 charged leptons Resonant production via λ 2 of smuon or sneutrino Cascade decay to LSP (neutralino) decay via λ 2 into 2 jets & lepton σ (λ 2 ) 2 Chiral superfields: L: lepton doublet superfield E: lepton singlet superfield Q: quark doublet superfield D: down-like quark singlet superfield λ, λ`, λ``: Yukawa couplings III. Phys. Inst. A
_ LLE Sparticle Production pair/associated gaugino production production is R-parity conserving 3 Each χ 3 leptons R-parity violating production s-channel: enhanced cross section 2 σ λ Only one gaugino _ LQD χ lepton + 2 jets
Pair/associated production (LLE) Two gauginos, possible cascade decay to χ χ χ is assumed to be the LSP Require prompt decay of χ λ > ~. 4 Final state: 4 charged leptons & 2 neutrinos Analyses require 3 leptons and missing transverse energy (eee or eeµ or eµµ or µµµ or eeτ) and ME T χ l l ν III. Phys. Inst. A
Pair/associated production (LLE) 5 Three LLE couplings λ 2, λ 22, λ 33 leading to final states eee or eeµ (λ 2 ) eµµ or µµµ (λ 22 ) eeτ (λ 33 ) Events / GeV 3 2 DØ, 36 pb - Work in progress Signal 5 * Z /γ ee, µµ * Z /γ ττ QCD (from data) WW, WZ, ZZ tt ll+x Data - 5 5 2 M ee [GeV] III. Phys. Inst. A
Pair/associated production (LLE) 6 [pb] σ NLO, σ 95%CL 2 - DØ, Lower limits on χ (χ ) up to 9 GeV (234 GeV) 5 2 25 3 DØ, 36 pb - Work in progress σ NLO (SUSY) expected limits λ 2 observed λ 22 observed observed λ 33 M ± χ [GeV] m = TeV -2 tan β =5, A =, µ> 2 6 8 2 4 6 M ± χ [GeV] M χ ± [GeV] Interpretation within the ± χ χ mass plane 26 22 8 4 Work in progress DØ, 36 pb - χ ± is LSP Exclusion domains obs. λ 2 obs. λ 22 LEP excluded obs. λ 33 exp. λ 2 exp. λ 22 exp. λ 33 2 6 4 8 22 M χ [GeV] To be submitted to Physics Letters B
LHC reach for non-zero LLE couplings 7 Reach for fb - λ 23 = -3 tanβ = 2 Tevatron LEP Atlas TDR qq χχ 4l+2ν+X
neutral long lived particles 8 Selection criteria Two muons with p T > GeV Require long lifetime of the neutralino 5 cm < (muon vertex primary vertex) < 2 cm (χ lifetime determined by λ 22 ) Require two muons from a displaced vertex data events found.75 ±. ±. events expected
neutral long lived particles 9 http://www-d.fnal.gov/run2physics/www/results/np.htm
Resonant Slepton Production via LQD Final state: 2-muon & 2-jet Three dominant signal channels:. 2. 3. ~ µ ~ χ µ µ ~ χ µ ~ ~ ν χ ± µ µ Analyze each channel separately Possible to reconstruct neutralino & slepton mass 2 ~ Cross section limits for every channel Combination within msugra III. Phys. Inst. A
Resonant Slepton Production via LQD possible to reconstruct neutralino and slepton mass number of events / 6. GeV 9 8 7 6 5 4 3 2 Reconstructed χ mass 5 5 2 25 3 35 4 inv. mass of µ 2, jet, jet 2 [GeV] 2,3,4, 2 ~ µ ~ χ µ µ ~ χ µ DO RunII preliminary Data µ χ µ, #58 µ χ µ, #58 2 ν χ ± µ, #58 µ * Z/γ ->µ µ QCD from Data * Z/γ ->ττ Di-Boson Y data signal x Z/γ * 6-3 GeV Z/γ * 5-6 GeV ~ ~ ν ~ χ ± µ µ tt QCD, b-tag data tt ll Work in progress DØ, 38 pb - Signal reference point : ~ m( l ) = 26 GeV m( ~ χ ) = GeV III. Phys. Inst. A
Resonant Slepton Production via LQD 2 µ mass [GeV] 5 45 4 35 3 25 2 5 Cross section limit ~ µ ~ χ µ D RunII preliminary DØ 38 pb -, Work in progress LEP Generated points 5 5 5 2 25 χ mass [GeV] 8 6 4 2 8 6 4 2 µ) [pb] χ ) BR(µ Limit σ(pp µ Interpretation within msugra (tanβ=5, µ<, A =) [GeV] m /2 6 5 4 3 2 τ is the LSP D RunII preliminary DØ, 38 pb - Work in progress q ~ r=8 GeV χ = GeV q ~ r=6 GeV χ =75 GeV ~ ~ l=3 GeV l=2 GeV q ~ q ~ LEP limit r=4 GeV Not r=2 GeV allowed Generated points 5 5 2 25 3 35 4 45 5 [GeV] m.2.4.6.8..2.4.6.8.2 95% CL Exclusion Contour for λ 2 To be submitted to Physical Review Letters III. Phys. Inst. A
Perspectives for the LHC Resonant slepton production 3 5σ reach σ [pb] σ LHC σ Tevatron λ 2 =.5 (Tevatron fb - ) σ LHC /σ Tevatron LHC @ 3 fb - Moreau, Perez, Polesello, Deliot
Conclusion 4 Presented searches for R-parity violating SUSY Pair/associated gaugino production (LLE) Neutral long lived particles (LLE) Resonant slepton production (LQD) No excess found in the data Very stringent limits were set Tevatron suffers from small cross sections and/or is constrained to a small parameter space At the LHC backgrounds will be challenging, especially for low (s)particle masses
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LHC reach for non-zero LLE couplings 6 Reach for fb - λ 23 = -3 tanβ = 2 Neutralino cτ (mm) Atlas TDR tanβ= CMS TDR Barbier et al. λ 2 =.5, tanβ=2, µ<, A = III. Phys. Inst. A
msugra parameter space 7 tanβ=5, µ<