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Radiative B-L symmetry breaking and the Z' mediated SUSY breaking. Takayuki Kubo (KEK) arXiv:0804.3933 [hep-ph] work in collaboration with Tatsuru Kikuchi (KEK). Outline. Introduction Review of the U(1) B-L extended MSSM Review of the Z-mediated SUSY breaking Results Summary. - PowerPoint PPT Presentation

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Radiative B-L symmetry breaking and the Z' mediated SUSY breakingTakayuki Kubo (KEK)arXiv:0804.3933[hep-ph]work in collaboration with Tatsuru Kikuchi (KEK)

SUSY 08, KoreaJune 17, 20081

SUSY 08, Korea

OutlineJune 17, 2008SUSY 08, Korea*IntroductionReview of the U(1)B-L extended MSSMReview of the Z-mediated SUSY breakingResultsSummary

SUSY 08, Korea

Introduction (1)June 17, 2008SUSY 08, Korea*The U(1)B-L extended MSSM has fascinating features.

Right-handed neutrinos are naturally introduced in order to cancel the anomalies.

B and L violating interactions are forbidden. Discrete symmetries (e.g. R-parity) are not needed !

Seesaw scale can be understood as a breaking scale of the U(1)B-L symmetry.

SUSY 08, Korea

Introduction (2)June 17, 2008SUSY 08, Korea*Z-mediated SUSY breaking need only an extra U(1) gauge multiplet.P. Langacker et.al., Phys. Rev. Lett. 100 (2008) 041802We can identify U(1)B-L as U(1)

We treat the U(1)B-L extended MSSM in a framework of the Z-mediated SUSY breaking.Radiative B-L symmetry breaking is achieved.Obtained mass spectra are much different from mSUGRA.

SUSY 08, Korea

Review of the U(1)B-L extended MSSM (1)June 17, 2008SUSY 08, Korea*SM and MSSM have a global U(1)B-L symmetry. But it can not be a local one, since Tr(B-L)30. Q : -1/3, Uc : 1/3, Dc : 1/3, L : -1, Ec : +1, H1 : 0, H2 : 0

Now, add the right-handed neutrinos Nc : +1 . Tr(B-L)3=0 and U(1)B-L can be a local symmetry !

Right-handed neutrinos are naturally introduced.

SUSY 08, Korea

Review of the U(1)B-L extended MSSM (2)June 17, 2008SUSY 08, Korea*U(1)B-L symmetry forbids B and L violating terms! UcDcDc : -1/3-1/3-1/30, LQDc : -1+1/3-1/30, LLEc : -1-1+10, etc.

U(1)B-L symmetry forbids B and L violating terms! Discrete symmetries (e.g. R-parity) are not needed !

SUSY 08, Korea

Review of the U(1)B-L extended MSSM (3)June 17, 2008SUSY 08, Korea*Superpotential

1 and 2 are MSSM siglets with B-L charges 1 : -2 and 2 : +2. (2 is necessary to cancel the anomaly produced by the fermionic component of 1.)

U(1)B-L symmetry forbids MNNcNc term !Instead, 1 gives the seesaw scale.

Seesaw scale can be understood as the breaking scale of the U(1)B-L symmetry.

new comers

SUSY 08, Korea

Review of the Z-mediated SUSY breaking (1)June 17, 2008SUSY 08, Korea*Extra gauge multiplet U(1) couples to both visible and hidden sectors.

U(1) gaugino acquires its mass at a scale s by a dynamics in the hidden sector.

All the soft-terms are induced by the U(1) gaugino mass through the RGE.

Visible

DynamicalSUSYBreaking

SUSY 08, Korea

Review of the Z-mediated SUSY breaking (2)June 17, 2008SUSY 08, Korea*At the scale s, only the U(1) gaugino acquires its mass. MSSM gauginos and scalars acquire their masses through the RGE.

Taking Ma100GeV, we have the U(1) gaugino mass106GeV.Scalar masses 105GeV.At low energy, all the scalars decouple (split SUSY).There is no SUSY flavor & CP problems in this model.

SUSY 08, Korea

SetupJune 17, 2008SUSY 08, Korea*Superpotential (I have already shown):

SUSY breaking terms: We adopt the Z-mediated SUSY breaking.Z is identified as ZB-L in this work.Only four input parameters ! =106GeV

SUSY 08, Korea

Radiative B-L breakingJune 17, 2008SUSY 08, Korea*Running behavior for the soft-mass of the 1 is shown below.

m21 goes into the negative region and develops a VEV.

Seesaw scale MN1 are generated dynamically. 105GeV~106GeV Only the B-L gaugino acquires its mass106GeV at s=109GeV

f=5f=4f=6f=71 scalar acquire its mass through the RGE.

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Gaugino MassesJune 17, 2008SUSY 08, Korea*Running behavior is shown below, where s=109GeV and gB-L=0.5 at =s.

Mass spectra are much different from mSUGRA (1:2:7) !The signals at the LHC experiments are rather exotic and interesting.Only the B-L gaugino acquires its mass106GeV at s=109GeV

gluinowinobinoB-L gaugino and all scalars decouples here!

SUSY 08, Korea

SummaryJune 17, 2008SUSY 08, Korea*Radiative B-L symmetry breaking works in a framework of Z-mediation.

The mass spectra for gauginos are much different from mSUGRA.

U(1)B-L extension is fascinating.

SUSY 08, Korea

June 17, 2008SUSY 08, Korea*

SUSY 08, Korea

Back upJune 17, 2008SUSY 08, Korea*

SUSY 08, Korea

Gaugino MassesJune 17, 2008SUSY 08, Korea*Running behavior is shown below, where s=109GeV and gB-L=0.5 at =s.

Mass spectra are much different from mSUGRA (1:2:7) !The signals at the LHC experiments are rather exotic and interesting.Only the B-L gaugino acquires its mass106GeV at s=109GeV

gluinowinobinoB-L gaugino and all scalars decouples here!

SUSY 08, Korea

Gaugino Masses (2)June 17, 2008SUSY 08, Korea*Gaugino masses as a function of the boundary value of gB-L.

Gaugino masses as a function of s.gluinowinobinogB-L is set to 0.5 at =s. gluinowinobinos is set to109GeV.

SUSY 08, Korea

SummarySUSY 08, KoreaU(1)B-L extension is fascinating.Existence of RH neutrinos makes U(1)B-L gaugeable.U(1)B-L symmetry forbids B and L violating terms.Seesaw scale can be understood as the breaking scale of U(1)B-L.

U(1)B-L extended MSSM with Z-mediation gives characteristic mass spectra. All the sfermion masses become very heavy (~105 GeV).The mass spectra for gauginos are much different from mSUGRA.

Radiative B-L symmetry breaking works in a framework of Z-mediation.

June 17, 2008*

SUSY 08, Korea

Brief Review of the U(1)B-L extended MSSM(4)June 17, 2008SUSY 08, Korea*Three features which I have shown Existence of RH neutrinos makes U(1)B-L gaugeable.U(1)B-L symmetry forbids B and L violating terms.Seesaw scale can be understood as the breaking scale of U(1)B-L are enough reason to study the gauged U(1)B-L.

I will show the radiative U(1)B-L symmetry breaking works and the mass spectra is characteristic in a framework of Z-mediated SUSY breaking.

SUSY 08, Korea