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Claudia Frugiuele Carleton University MMRSSM Lepton number as R symmetry, Sneutrino as down type Higgs Edinburgh 13/04/2011 q \\\AQ. in collaboration with Thomas Grégoire. Outline. SUSY, MSSM, R p Continuous R symmetry, MRSSM Our model: MoreMinimalRSSM Experimental constraints
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Claudia FrugiueleCarleton UniversityMMRSSMLepton number as R symmetry,Sneutrino as down type HiggsEdinburgh 13/04/2011q\\\\\\AQ in collaboration with Thomas Grégoire
Outline • SUSY, MSSM, Rp • Continuous R symmetry, MRSSM • Our model: MoreMinimalRSSM • Experimental constraints • MMRSSM features, and pheno
With same mass and quantum number SUPERSYMMETRY • Most popular solution to the hierarchy problem. • Symmetry between fermions, and bosons With same mass and quantum number
SM fermionbosonic, spin 0, superpartner, sfermions. SM boson spin ½ fermion gauge boson, gaugino. Higgs, higgsino SUPERFIELD contains Fermion/Boson and its SUSY partner Boson/ Fermion
MSSM (Minimal Supersymmetric extension of the SM) Each SM field is promoted to a superfield.
SUSY BREAKING We do not see scalar electrons or fermionic gluons! Supersymmetry should be broken. Still solution to hierarchy problem as long as SUSY-breaking operators are “soft” (d<4).
SOFT TERMS Mass and mixing term for sleptons, squarks and higgses. 2) Majorana mass for the gauginos 3) Trilinear couplings
SUSY HIGGS SECTOR Hu mass to the up type fermions Hd mass to the down type fermions. MSSM Higgs sector two higgs doublets model Yukawa interactions contained in the superpotential, holomorphic function of the superfields
SUSY HIGGS SECTOR Hdsame gauge numbers of a lepton field, but the sneutrino can’t be a Higgs field. Is it possible Hd L ?
No it is not. Hd is necessary to cancel the Hu anomalies. SneutrinoVeV violates lepton number, constraints on the neutrino mass impose the VeV to be very small.
MSSM SUPERPOTENTIAL to give mass to the Higgsino But Lepton and baryon number are not accidental symmetries ex. fast proton decay
Proton decay Majorana neutrino mass fig. hep-ph/0406039v2 Strong bounds on these couplings!
R parity • Typical solution: impose a discrete symmetry called R parity Fermionic and bosonic component of a superfield have different R parity! • SM particle even under R parity • SUSY partners odd under it Distinctive pheno at the LHC!
Model with R parity violation We introduce these terms in the superpotential Couplings are highly constrained from the experimental bounds ( neutrino mass) Interesting and different pheno at the LHC.
U(1)R continuous R symmetry R parity contained in U(1) R continuous symmetry. U(1)R acts differently on the fermionic and bosonic component of a field:
U(1)R symmetry Gauge superfield, fixed R chargeR gauge boson=0 R gauginos=1SU GauginosMajorana mass are forbidden by R symmetry MSSM is not R symmetry invariant Gauginos should be Dirac fermions!
Dirac Gauginos New Adjointssuperfields for each SM gauge group to give Dirac mass to the gauginos Supersoft SUSY breaking operator, Fox, Nelson, Weiner, 2002 D term spurion
MRSSM arXiv::0712.2039 [hep-ph] Enlarged Higgs sector, two new doublets Ru Rd New Adjointssuperfields for each SM gauge group to give Dirac mass to the gauginos
MRSSM Higgs sector W superpotential R charge 2 Forbidden by R symmetry Necessary to give mass to the higgsino
MRSSM features 1)Dirac gauginos 2)No left/right mixing as trilinear soft couplings are forbidden by R symmetry 3)Enlarged Higgs sector, inert doublets 4) Large flavor violation compatible with bounds Is this the Minimal R symmetric SSM?
MMRSSM More Minimal MRSSMR symmetry as Lepton number,sneutrino as down type Higgs Hd La a=e or μ or τ
We economized the particle content of the model respect the MRSSM! One of the sneutrino plays the role of the down type Higgs Hd Necessary to cancel anomalies and to give mass to the Higgsino
U(1)R lepton number,ex. here electron number Ex:Qi R charge 1, fermion R charge 1-1=0 SM particle don’t carry R charge beside electron and its neutrino. SUSY partners carry all R charge besides the slectron, and the electronic sneutrino
OUR MODEL:The electronic sneutrino does not carry R charge/lepton number A sneutrinoVeV does not induce a neutrino mass!
More minimal particle content of the model respect the MRSSM! Just two Higgs doublets as in the MSSM, one is inert as the lepton field gives mass to the down type fermions Need just to add the adjointssuperfields to the MSSM spectrum
OUR MODEL:MMRSSM superpotentialDown type Yukawa couplings= Rp violating couplingsSU Higgsino mass is nulll. Yukawa coupling for the electron is generated by SUSY breaking
Rp parity and our symmetryRp violating couplingsStandard Rp parity is violated as our R symmetry is not the usual R symmetry (ex:MRSSM), but it is one of the lepton numberSU
MMRSSM Experimental constraints: No constraints from neutrino mass, but.. • Neutrino and electron mixes with adjoints fermions. • Other Rp violating couplings bounds • R symmetry breaking by anomaly mediation • Cosmological bounds
Leptons mixing a=e or μ or τ vasneutrinoVeV
Leptons mixing • Constraints from the gauge bosons couplings • Lepton universality violation
Leptons mixing • Strongest bounds from the Z0 coupling GeV
SneutrinoVeV bounds a=e a=μ,τ Heavy gauginos, large sneutrinoVeV
Bounds from Rp violation Down type Yukawa couplings = Rp violating couplings, EWPM bounds, no neutrino bounds!
TrilinearRp violating couplings induce neutrino mass, in our case they don’t. Majorana neutrino mass forbidden by R symmetry fig. hep-ph/0406039v2 Less strong bounds!
Indirect bounds from EWPM Contribution to GF Semileptonic Meson decay fig. hep-ph/0406039v2
Lower bound on sneutrino VeV Tau Yukawa Bottom quark Yukawa Very high tanβ region excluded
Less stringent bounds! ex bottom quark yukawa Our case Neutrino bounds can have a sizeable branching ratio!
R symmetry broken by Anomaly mediation Majorana mass for gauginos Trilinear scalar coupling Majorana mass for the neutrino.
Neutrino mass generated by Left/Right mixing generated by anomaly mediation fig. hep-ph/0406039v2
R symmetry broken by Anomaly mediation Bounds on SUSY breaking Scale, F <1016 (GeV) 2 Gauge mediation
Low scale SUSY breaking: Gauge mediation Low scale SUSY breaking No gravity mediation. R-symmetric gauge mediation Several models (J. Amigo et al., JHEP 0901 (2009) 018, K.Benakli,M.GoodsellNucl.Phys. B816 (2009) 185–203,L.M Carpenter arXiv:1007.0017.)
Gravitino LSP • Unstable • Possible Dark matter candidate BUT…
Gravitino LSP The relic density should be very small Very low reheating temperature required!
Gravitino LSP GeV TR below the SUSY threshold
Summary: The sneutrinoVeV can be quite large for fairly heavy gauginos, Stronger Rp violation than in the usual scenario, expect phenomenological consequence, Low scale SUSY breaking Gravitino is not dark matter
Outline • Mu Bmu problem • Yukawa coupling for the Higgs/Lepton • Electroweak symmetry breaking • LHC Phenomenology
Mu/Bmu problem Mixing term Higgsino mass Naturalness X spurion field
Mu/Bmu problem Gauge mediation One loop Fine tuning! One loop