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Electric Dipole Moments in PseudoDirac Gauginos

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Electric Dipole Moments in PseudoDirac Gauginos

Minoru Nagai

(ICRR, Univ. of Tokyo)

Phys.Lett.B644:256-264 (2007)

Collaborated with:

J.Hisano (ICRR)

T.Naganawa (ICRR)

M.Senami (ICRR)

Mar. 1, 2007

KEK Annual Theory Meeting on Particle Physics Phenomenology (KEKPH2007)

Majorana gaugino mass

- Low energy SUSY models are the most well-motivated model beyond the Standard Model.
We haven’t discovered SUSY particles yet.

SUSY must be broken.

- Hierarchy problem
- Dark Matter Candidates
- GUT, Light Higgs, Radiative EWSB…

Gaugino mass

Generation of gaugino mass terms by singlet fields is upsetted by

- SUSY CP Problem
- Polonyi Problem

CP & Pviolating Dim 5 operator

To solve this problem, we need to

- suppress the phases
- prepare heavy SUSY particles
- extend MSSM

- SUSY CP Problem(Constraint from EDMs)
Complex parameters in MSSM

O(1) CP phases of these parameters induce too large EDMs.

ex) Constrained MSSM

From neutron EDM experiments,

Small with unchanged

These problems may imply that

there is no singlet fields that mediate SUSY breaking.

- Polonyi Problem

(Constraint from cosmology)

- Overclosure of the universe ⇒ Late time decay
- Gravitino Overproduction

Destroy the success of BBN

⇒

Is it escaped by introducing dynamical symmetry breaking scale?

⇒No. It can’t be operative since the linear term of singlet fields

destabilize the potential minimum.

[M.Ibe, Y.Shinbara and T.Yanagida (2006)]

Anomaly mediation

How about gaugino masses?

Gaugino can have Dirac masses and get small majorana masses

PseudoDirac Gaugino (PDG)

Suppression of EDMs

We disscuss this PseudoDirac Gaugino (PDG) models for a framework to solve the SUSY CP problem

Introduction

PseudoDirac Gaugino (PDG) Models

EDMs in PDG models

Conclusion

“No Singlet”

We assume

Majorana Gaugino mass

cf) sfermion soft masses

Dirac Gaugino Mass terms

[P.Fox, A.Nelson and N.Weiner(2002)]

SM gauge fields

Adjoint fields

Hidden sector U(1) gauge field

U(1)R charge :

Supersymmetric Adjoint fields mass

(model dependent)

vanish in U(1)R symmetric limit

PseudoDirac Gaugino Models

60

50

40

30

20

10

0

0

2.5

5

7.5

10

12.5

15

17.5

Bachelor Fields

[P.Fox, A.Nelson and N.Weiner(2002)]

Due to the existence of adjoint fields, gauge coupling unification is spoiled.

⇒Bachelor Fields are introduced to recover the unification.

Adjoint fields + Bachelor fields = GUT multiplet

For the successful unification, bachelor masses must be

U(1)Y

SU(2)

Here we adopt SU(5) GUT and take

SU(3)

Sfermion soft masses

We take universal mass at the GUT scale.

Radiative correction by Dirac mass terms are finite and don’t have logarithm.

(“supersoft”)

A terms

“No Singlet”

Using above symmetries we take

We can also take and real

CP phases in PDG models

Complex parameters :

D.o.f. for rephasing of adjoint fields in addition to and .

GUT & universality of gaugino masses and A terms

# of physical phases : 7 - 3 = 4

CP phases in the MSSM

CP phases are aligned.

Additional Phases that appear by extending gaugino sector

This phase contribute to the Weinberg operator at 2 loop level

The phase of gaugino majorana masses

Current bounds

Neutron EDM :

Electron EDM :

: Universal Dirac gaugino mass at GUT scale

: Universal sfermion soft mass at GUT scale

EDMs are suppressed by small gaugino majorana masses

The phase of supersymmetric adjoint masses

Current bounds

Neutron EDM :

Electron EDM :

: Universal Dirac gaugino mass at GUT scale

: Universal sfermion soft mass at GUT scale

U(1)R symmetric limit

Supersymmetric adjoint masses must be small to suppress EDMs

We discussedelectric dipole moments in pseudoDirac gaugino modelswhere new adjoint fields are introduced and gauginos have Dirac mass terms.

- The contributions of MSSM CP phases to EDMs are suppressedsince A terms and gaugino masses are smallin this model.
- New CP phases are introduced by extending the gaugino sector. These phases may contribute to EDMs significantly but they vanish in the exact U(1)R limit.
- The predicted values of EDMs are within the reach of near future experiments and we can check this scenario.

( : model dependent)

We assume

Supersymmetric Adjoint fields mass

U(1)R charge :

vanish in the superpotential in the U(1)R symmetric limit

But they can be generated in the

Ex.)

chiral compensator

Even if is zero at tree level, they can be generated radiatively. For example, interactions with heavy chiral field X and X,

induce .

Some mechanism may be needed to suppress this term.