mitsuru kakizaki- introduction to kk dark matter

8/3/2019 Mitsuru Kakizaki- Introduction to KK dark matter

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February 26, 2008 Mitsuru Kakizaki

Introduction to KK dark

matterMitsuru Kakizaki (Bonn University)

February 26, 2008

Dark Matter VisitorsProgram

Refs: Original idea of UED: Appelquist, Cheng, Dobrescu, PRD67, 035002(2000)Recent review on UED: Hooper, Profumo, Phys.Rept. 453 (2007)

Resonance efect on the KK dark matter relic abundance:MK, Matsumoto, Sato, Senami, PRD71, 123522 (2005);MK, Matsumoto, Senami, NPB735, 84, (2006); PRD74, 023504 (2006)


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February 26, 2008 Mitsuru Kakizaki 2

MotivationNon-baryonic dark matter

[http://map.gsfc.nasa.gov]

Neutralino (LSP) in supersymmetric (SUSY)models

1st KK mode of the B boson (LKP)in universal extra dimension (UED) models

etc.

My talk

Cosmological observations

Stable (long-lived), neutral, colorless particles withweak-scale mass and weak interaction are good

candidatesknown as weakly interacting massive particles(WIMPs) :

What is the constituent of dark matter?

No candidate particle in the standard model of particle physics


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Thermal production of cold relics :

Typical annihilation cross section of WIMPs with :

WIMP abundance

Increasing

Decoupling

Thermal

equilibrium

Co-moving number density

The predicted thermal relic density is in the desiredrange!!!

were in thermal equilibriumin the early universe

After the annihilation rate dropped below the expansion rate,the number density per comoving volume is almost fixed


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dimension(UED) models

Idea: All SM particles propagate inflat compact spatial extra dimensions

[Appelquist, Cheng, Dobrescu, PRD64 (2001) 035002]

Dispersion relation:

Momentum along the extra dimension= Mass in four-dimensional viewpoint

compactification withradius :

Mass

spectrumforquantized

Momentum conservation in the extra dimension

Conservation of KK number at each vertex

Macroscopic

MicroscopicMagnify

KK tower


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orbifold

Conservation of KK parity:The lightest KK particle (LKP) is stable

The LKP is a good candidate for dark matter

c.f. R-parity and LSP

Chiral zero-mode fermions

Minimal UED (MUED)model

Only two new parameters in the MUED model:: Size of extra dimension

: Scale at which boundary terms vanish

More

fundamentaltheory

The Higgs mass remains a free parameter


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Mass spectra of KK statesKK particles are degenerate in massat tree level:

[From Cheng, Matchev,Schmaltz,PRD66 (2002) 036005]

Radiative corrections relaxthe degeneracy

1-loop corrected massspectrumfor the 1st KK level

Compactification

5D Lor. inv.Orbifolding Trans. Inv. in 5th dim.

Lightest KK Particle (LKP): Degenerate in mass

(mixture of )

Coannihilation plays an important role

Resonance enhancement in scattering processes


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SUSYSUSY vs UED

Majorana fermion

(mainly ) (mainly )

chirality-suppressed

Spin-1 boson

LSP(LKP) annihilationinto fermion pairs:

LSP(LKP) in

many cases:

Spin of LSP(LKP):

No helicity suppression

UED Mass spectra

and spin

SM

SM

SparticleSame spin

Diferent spin

Higher KKmodes



:

High energy experiments

KK parity weaker constraints

[Flacke, Hooper, March-Russell, Macesanu PRD73

(2006);Erratum: PRD74 (2006); Gogoladze, PRD74(2006)]

for

[Haisch, Weiler, PRD76(2007)]

Precision tests:

Indirect constraints:

Direct searches: Tevatron (CDF Run IB):

LHC: discovery reach in the channel:

[Cheng, Matchev, Schmaltz PRD66 (2002)

056006]

[Lin, FERMILAB-THESIS-2005-69,UMI-31-94684]



Thermal relic abundance

Includingresonances

Withoutresonances

Resonance enhancement isefectivefor all Higgs masses

[MK, Matsumoto, Senami, PRD74, 023504(2006)]

in theNR limit

Resonance

Coannihilation

Calculation of the LKPabundance iscomplicated for every parameterset:



Direct detection

Spin-independen: Spin-dependent:

[From Servant, Tait, NJP4, 99 (2002)]

[Cheng, Feng, Matchev, PRL89

(2002);Servant, Tait, NJP4, 99 (2002)]

Enhanced by an s-channelpole

Dicult toobservein most cases



Indirect detection

Exotic gamma rays from the galactic center:

Positrons from annihilations in the galactic halo:

Final state radiation fromdominates at higher energies in thespectrum

No helicity suppression in annihilation of

A sharp peak at in the spectrumexpected [Cheng, Feng, Matchev, PRL89

(2002)]

[Cheng, Feng, Matchev, PRL89 (2002);Bergstrom, Bringmann, Eriksson, Gustafsson, PRL94

(2005)]



Discussion Remarkable features of UED models:

Radion stabilization, boundary terms, KK parity anomaly

KK gravitons, baryogenesis, inflation

Problems:

KK particles are degenerate in mass at each KK level

Phenomenology in non-minimal UED models (neutrino mass,d>5, )

Comparison of UED and SUSY Davids talk

Threshold singularity in KK particle

annihilation

The spins of KK particles are the same as the corresponding SMparticles Existence of higher KK modes


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Questionnaire

A) Yes

B) No

Do you think that the dark matter is made of WIMPs?


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Backup slides


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Contrasting SUSY and UED atCLIC (Multi-TeV collider)

[Battaglia, Datta, De Roeck, Kong, Matchev, hep-ph/0502041]

missing energy > 2.5 TeV transverse energy < 150GeV

event sphericity > 0.05 missing trans. energy > 50

Event seletion: SM background:

(small polar angle)

MSSM parameters are

adjusted to reproduce UEDkinematics

Comparison of

within UED

in SUSY

UED parameters:

Missing

Rad. cor.


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Angular distributionand spin measurements

: Spin 1/2

: Spin 0

: signal+

background: signal

UED:

SUSY:at

Factor

[From Battaglia, Datta, De Roeck, Kong, Matchev, hep-ph/0502041]


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Discrimination of UED fromSUSY

Cross section for

resonance

Including

beamstrahlung

Photon energy spectrum in

c.f. SUSY: at threshold region, no sharp peak due to

resonance

[From Battaglia, Datta, De Roeck, Kong, Matchev, hep-ph/0502041]


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KK graviton problemFor,

Introduction of right-

handedneutrinos of Dirac type

[From Matsumoto, Sato,Senami, Yamanaka, PLB647,466 (2007)]

LKP in the MUED

KK gravitonLKP region

Attempts:

Emitted photons

woulddistort the CMBspectrum

[Feng, Rajaraman, Takayama PRL91(2003)]

decays at latetimes

is a DMcandidate

[Matsumoto, Sato, Senami, Yamanaka, PRD76(2007)]

WMAP data can be aslow as


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UED

SUSY

R parity stabilizes the LSP

Kinematics of 1st KK modes resembles that ofsuperparticleswith degenerate mass

KK parity stabilizes the LKP Superparticle mass 1st KK mode mass

SUSY vs UED

SUSY breaking mass

SM

SM

Sparticle Same spin Diferent spin

(UED is called Bosonic supersymmetry)


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LHC:[Cheng, Matchev, Schmaltz PRD 66 (2002) 056006]

Signals of 1st KK modes are similar to those ofsuperparticles

Discovery reach for minimal UED:

UED vs SUSY

Future colliders are promisingfor distinguishing UED and SUSY

Observation of ef

ects caused by second KK modes Determination of spins of new particles


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Parameters in UED models

c.f. minimal SUGRA:

: Cutofscale: Size of extra dimension : Higgs boson mass

Kaluza-Klein expansion (Fourier expansion):

and

Only three free parameters in minimal UEDmodel:

Zero modes areidentified

with SM fields


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Minimal UED

Conservation of KK parity [+ (--) for even (odd) ]The lightest KK particle (LKP) is stable

c.f. R-parity and the LSP in SUSY models

Reflection sym. under

Experimental limit on is weakerthan other extra-dimensional models:

Electroweak precisiontests

Single KK particle cannot be produced

{

Dark matter

In 5D spacetime, spinor representationhas 4 complex components

Chiral fermions in4De.g.

Dirac

Dirac

Chiral


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Particle contents in minimalUED

Electroweak symmetry breakingefectsare suppressed for higher KKmodes

KK level

New particles:

Massless

Massive

Massive(Mass)

Dirac

Gauge bosons Fermions

Real scalar

Scalars

SM particles:(Mass )

Dirac

Chiral

Complex

scalar


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Interactions in UED models e.g. gauge interaction offermion:

KKexpansion

5D 4DFor

SM

KK


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Radiative corrections tomass spectra of KK modes

[Cheng, Matchev, Schmaltz, PRD66, 036005(2002)]

One-loop corrected massesof 1st KK modes

c.f. SUSY: Universal soft mass at cutof scale Mass splitting at weakscale

Tree level massesspectrumof 1st KK modes


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Thermal relic abundance

Includingresonances

SUSY (cMSSM)

[From Ellis, Olive, Santoso, Spanos, PLB565 (2003)

176]

UED (minimal UED)

[Kakizaki,Matsumono,Senami,

KK Higgscoannihilationregion

Bulkregion


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Radiative correctionsKK number violating couplings

pair production

is naturally enhanced by-resonance in the s-channel

Second KK particle physics

Signal of2 lepton + large missing energy is expected tohave large cross section and be almost background

free

(2nd KK mode mass)(1st KK mode mass)

[MK, Matsumoto, Sato, Senami, hep-ph/0502059]

e.g.

New


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Thresholdsingularity

Threshold cross section for KK quarkoniumat linear collider

[MK, Matsumoto, Okada, Yamashita, ]

IdeaKK quarkonium

KK quarkonium crosssection

for small decaywidth

Energy of bound state:


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Collider signatures at LHC[Cheng, Matchev, Schmaltz PRD66 (2002)056006]

Discovery reachDecay chains of 1st KK modes


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Muon energy spectrum

[From Battaglia, Datta, De Roeck, Kong, Matchev, hep-ph/

0502041]


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Threshold scan Cross section for


0502041]


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F b 26 2008 Mit K ki ki 32

Radiative return to


0502041]

Photon energy spectrum in

mitsuru kakizaki- introduction to kk dark matter

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