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March 2005 Theme Group 2 Unified TeV Scale Picture Unified TeV Scale Picture of Dark Matter and of Dark Matter and Baryogenesis Baryogenesis R. N. Mohapatra University of Maryland Neutrino Telescope 2007, Venice (K. S. Babu, S. Nasri and R. N. M., hep- ph/0612357)

Unified TeV Scale Picture of Dark Matter and Baryogenesis

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Unified TeV Scale Picture of Dark Matter and Baryogenesis. R. N. Mohapatra University of Maryland Neutrino Telescope 2007, Venice (K. S. Babu, S. Nasri and R. N. M., hep-ph/0612357). Current Prevalent Thinking. - PowerPoint PPT Presentation

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Page 1: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Unified TeV Scale Picture of Dark Unified TeV Scale Picture of Dark Matter and BaryogenesisMatter and Baryogenesis

R. N. MohapatraUniversity of Maryland

Neutrino Telescope 2007, Venice

(K. S. Babu, S. Nasri and R. N. M., hep-ph/0612357)

Page 2: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Current Prevalent ThinkingCurrent Prevalent Thinking• Dark matter is either LSP of Supersymmetry

or lightest Kaluza-Klein Mode in models with extra Dimensions with R~TeV^-1 or perhaps the axion.

• Origin of Matter comes from different physics i.e. from Right handed neutrino decay in Seesaw models for neutrinos involving sphalerons.

• Unrelated physics

Page 3: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Dark Matter issues in MSSMDark Matter issues in MSSM

• Getting the dark matter to fit into MSSM requires fine tuning:

(i) Either Bino-Higgsino mixing must be fine tuned to get the right relic density

Or (ii) Co-annihilation needed where stau and LSP nearly degenerate (within 20 GeV): requires adjustment of m^2_0.

Page 4: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Co-annihilation-DetailsCo-annihilation-Details

•LSP-Stau fine tuning:

GeVM 20

Page 5: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Dark Matter Constraints on MSSMDark Matter Constraints on MSSM

129.094. 2 hCDM

Page 6: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Constraints at Higher tan betaConstraints at Higher tan beta

Page 7: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Perhaps Gravitino Dark matterPerhaps Gravitino Dark matter• Feng Takayama, Rajaraman;,

• LSP Gravitino : Another alternative.

Escapes direct detection.

Similar constraints

on MSSM parameter

space

Ellis, Olive, Santoso, Spanos

Page 8: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Yet SUSY has its own appealYet SUSY has its own appeal• It stabilizes the weak scale against

radiative corrections;• It leads to unification of gauge

couplings.• So is there an extension of MSSM that

preserves these good features, broadens the parameter space of MSSM and gives a unified picture of dark matter and origin of matter and neutrino masses?

Page 9: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Neutrino mass extension of MSSMNeutrino mass extension of MSSM• Add three right handed neutrinos with heavy

Majorana masses:• New superpotential:

Leads to seesaw formula for neutrino masses:

N-decay via leptogenesis leads to baryon asymmetry.

MNNNLHhWW uMSSM

R

D

M

mM

2

Page 10: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Two points about this model:Two points about this model:

• Neutrino Observations do not require three RH neutrinos- two are enough. (the so-called 3X2 seesaw)

• SUSY seesaw models for leptogenesis have some problems !!

Page 11: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Issues with leptogenesis modelsIssues with leptogenesis models

• In typical scenarios, often the lightest RH neutrino masses are higher than the reheat temperature after inflation coming from gravitino abundance- posing a problem.

(Davidson, Ibarra have a lower bound on MN of GeV ;

also true in many interesting SO(10) models.

The upper bound on T-reheat for generic TeV scale gravitinos

is < GeV ; Kohri, Mori,Yotsuyanagi )

910

710

Page 12: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Upper bound on T-reheat (Kohri et al paper)Upper bound on T-reheat (Kohri et al paper)

Page 13: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

New ModelNew Model

• Could it be that only two of the RH neutrinos are heavy and the third one is very light (i.e. TeV scale )

• We show that• (i) such a model can naturally arise from a

simple symmetry;• (ii) In this case, one can have a unified TeV

scale model for both baryogenesis, neutrino masses and dark matter.

Page 14: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

New proposal: XMSSMNew proposal: XMSSM• 3x2 seesaw model with the third RH neutrino

in the TeV scale and decoupled from the neutrino sector:

• Plus a pair of color triplets: and with couplings:

Impose R-parity symmetry as in MSSM.

This simple extension provides a remarkably natural model for dark matter, neutrinos and baryogenesis and has testable predictions !!

X X

XddXNuW lc

kc

klic

i NNM N XXM X

Page 15: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Grand unification of this modelGrand unification of this model• If and belong to full SU(5) multiplets

10 and 10-bar , Coupling unification is not affected.

• Only the value of then final value of the GUT coupling changes. - Couplings motivated by SO(10) GUT: , part of 120 Higgs and 16 .16. 120 coupling

leads to our interactions. - Discrete symmetry guarantees the third RH

N decoupling naturally. (see later)

X X

X X

Page 16: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Baryogenesis and Dark MatterBaryogenesis and Dark Matter

• Mass ordering among particles:

,

MSUGRA boundary condition implies that

Where are the real and imaginary parts of .

is stable and is the dark matter candidate. N unstable and gives

TeVM XX , NNsleptonssquarks MM ~,, GeV100

21~~ ,NNN

MMM 2,1

~N N

~

1

~N

nnB /

Page 17: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Scalar mass runnning to weak scale MSSMScalar mass runnning to weak scale MSSM

N~

Assume scalar masses same at high scale.

Page 18: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

DecayDecay mode of N-fermion mode of N-fermion

• X-exchange gives a decay

+ anti-quark modeccc dduN

N cu

X cd

cd

2

)(

X

kljjklN

MG

Page 19: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Post Sphaleron BaryogenesisPost Sphaleron Baryogenesis

• Babu, R. N. M., Nasri, Phys Rev. Lett. 97, 131301 (2006)

• Out of equilibrium condition (one of three Sakharov conditions)

satisfied at:

For , N goes out of equilibrium below its mass and is ready to generate baryons via its CP and baryon violating decay.

PldduN M

Tg

ccc

2

222

53

)11

()(19221

1)(

21 XX MMMTrN

42/12 10])}[({ Tri

Page 20: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Baryogenesis DiagramsBaryogenesis Diagrams• N decay to 3 quarks and anti-quarks are different

due to CKM CP violation and interference between tree and one loop diagrams: (no sphalerons needed)

+

cu

cd

cd

Page 21: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Estimate ofEstimate of B

||

sin

4 222

221232

W

ubbcB

M

Vmm

Dominant contribution is from W-Dominant contribution is from W-exchange and is:exchange and is:

Gives:Gives:

Right order.Right order.

222

23218

||103

B

Page 22: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

As Scalar dark matterAs Scalar dark matter

1

~N 1

~N

1

~N

Relic density:Relic density:Annihilation channelAnnihilation channel

Cross section:Cross section:

For reasonable choice of parameters, cross For reasonable choice of parameters, cross section is of order of a 0.1 pb and gives the section is of order of a 0.1 pb and gives the right relic density.right relic density.

ccuu

4

22 ||)(

8

1

XM

pv

Page 23: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Releases the SUSY parameter spaceReleases the SUSY parameter space

not

dconstraine

not In NXMSSMIn NXMSSMnot

///////\\\\\\\\\\/////

Page 24: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Direct detection of dark matterDirect detection of dark matter

2

4

241

~

641

A

ZA

M

m

X

p

pN

Cross section about 10^(- 45) cm^2-Cross section about 10^(- 45) cm^2-In the observable range.In the observable range.

Page 25: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

A crucial experimental testA crucial experimental test

• N-N-bar oscillation: Diagram involves Majorana N exchange

• Effective strength:

• Will lead to N-N-bar osc via the s-content in neutron.• Transition time expected to be around 10^8 sec.

NXB MM

G4

1212

cccccc sdusduO

Page 26: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Present expt situation in N-N-bar Osc.Present expt situation in N-N-bar Osc.

Range accessible to current reactor fluxes:

Present limit:ILL experiment: Baldoceolin et al. (1994)

New proposal by Y. Kamyshkov et al for an expt at

DUSEL GOAL:

Figure of merit ~

.sec108 nn

.sec1010 1110 2

nn

tFlux

.sec1010~ 118 nn

Page 27: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Scheme of N-Nbar search experiment at DUSEL

Dedicated small-power TRIGA research reactor with cold neutron moderator vn ~ 1000 m/s

Vertical shaft ~1000 m deep with diameter ~ 6 m at DUSEL

Large vacuum tube, focusing reflector, Earth magnetic field compensation system

Detector (similar to ILL N-Nbar detector) at the bottom of the shaft (no new technologies)

Page 28: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Tests at LHC--Tests at LHC--New signaturesNew signatures

(i) Monojet + missing energy signals from X-production in pp collision.

(Missing energy is N)

(ii) 4 jets + missing energy from:

NqXqq

qqqq~~

c c

Nqq ccNqq cc N

~N~

Page 29: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Symmetry giving this modelSymmetry giving this model

Consider Seesaw model for neutrinos invariant under a that exchanges only

RH neutrino field decouples

from seesaw formula which now becomes a 3x2 seesaw involving and .

Our singlet field then is N= ;

N mass can be chosen in the 100 GeV range without affecting neutrino masses or other low energy observations !!

,2RZ NN

)(2

1 NNN

eN )(2

1 NNN

)(2

1 NNN

Page 30: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

Tests in neutrino mixingsTests in neutrino mixings

• 3X2 seesaw with 2 RH neutrinos:

• For normal hierarchy, it necessarily predicts nonzero and of order

; hence testable.

- Inverted hierarchy if is zero.

13

solar

atm

m

m2

2

13

Page 31: Unified TeV Scale Picture of Dark Matter  and Baryogenesis

March 2005Theme Group 2

ConclusionConclusion• A simple extension of MSSM that gives

a unified TeV picture of dark matter and baryogenesis. Less fine tuned than MSSM. Embeddable into a seesaw model for neutrinos.

• Opens up MSSM parameter space.• SUSY phenomenology (e.g. LHC signal)

very different from MSSM.• Crucial test is Neutron-anti-neutron osc

time in the observable range.