EWIMP dark matter detections EWIMP dark matter detections Shigeki - - PowerPoint PPT Presentation

• Phys. Rev. D71: 063528, 2005
• Phys. Rev. Lett. : 92: 031303, 2004
• Phys. Rev. D67: 075014, 2003

EWIMP dark matter detections EWIMP dark matter detections

Collaborated with Junji Hisano (ICRR, University of Tokyo) Mihoko Nojiri ( YITP, Kyoto University ) Osamu Saito (ICRR, University of Tokyo) Collaborated with Junji Hisano (ICRR, University of Tokyo) Mihoko Nojiri ( YITP, Kyoto University ) Osamu Saito (ICRR, University of Tokyo)

Shigeki Matsumoto

HIGH ENERGY ACCELERATOR RESEARCH ORGANIZATION (KEK)

Shigeki Matsumoto

HIGH ENERGY ACCELERATOR RESEARCH ORGANIZATION (KEK)

Dark Matter Abundance Dark Matter Abundance Mean density of matter and baryon Mean density of matter and baryon Existence of non-baryonic (cold) dark matter Existence of non-baryonic (cold) dark matter

6

• 7

2 . 9 1 0 G e V / 4 . 6 1 0 G e V / c c c c

B M

ρ ρ

−

≈ × ≈ ×

Beyond SM Physics Beyond SM Physics Constituent of dark matter Constituent of dark matter

=

Results from recent cosmological observation

Concrete example Neutralino in Minimal SUSY SM Concrete example Neutralino in Minimal SUSY SM EWIMP Dark Matter EWIMP Dark Matter We consider non-singlet dark matter (a neutral component of multiplet) Electroweak charged WIMP = EWIMP We consider non-singlet dark matter (a neutral component of multiplet) Electroweak charged WIMP = EWIMP

(2) L SU

01 02 03 04 d u

Z B Z W Z H Z H χ = + + +

• χ
• g

W,Z

• partner

(2)L SU

Triplet Doublet We focus on signatures in EWIMP dark matter detections. ( Direct detection, Indirect detection using ) Interesting phenomena occur in these detections !! We focus on signatures in EWIMP dark matter detections. ( Direct detection, Indirect detection using ) Interesting phenomena occur in these detections !!

(2)L SU , e γ

+

Direct detection for EWIMP dark matter Direct detection for EWIMP dark matter

2 2 43 2 2

3 10 100

SI

cm GeV M μ σ

− −

⎛ ⎞ × ×⎜ ⎟ × ⎝ ⎠ ∼

q q

χ

• q

~

χ

• χ
• q

If the EWIMP mass is large enough, the cross section at tree level is suppressed by new physics scale If the EWIMP mass is large enough, the cross section at tree level is suppressed by new physics scale

h, H

E

Nuclear recoil after EWIMP-nucleus scattering Triplet EWIM (Wino-like dark matter) Diagrams for Spin-independent Int.

gaugino-higgsino mixing squark mass

Non-decoupling interaction at 1-loop level Non-decoupling interaction at 1-loop level

Intermediate chargino particle in these diagrams are almost On-shell. There are no suppression at each vertex in these diagrams. Intermediate chargino particle in these diagrams are almost On-shell. There are no suppression at each vertex in these diagrams.

χ

• χ
• q

q q’ W W W W h, H

At 1-loop level, there are some diagrams not suppressed by new physics scale. At 1-loop level, there are some diagrams not suppressed by new physics scale. In the extremely heavy EWIMP case, the 1-loop diagrams are larger than diagrams at tree level !! The 1-loop diagrams give the lower limit of the collision cross section. In the extremely heavy EWIMP case, the 1-loop diagrams are larger than diagrams at tree level !! The 1-loop diagrams give the lower limit of the collision cross section.

EWIMP-Nucleon cross section including 1-loop diag. EWIMP-Nucleon cross section including 1-loop diag.

47 2

( 10 ) cm

−

×

Cross section m = 200 GeV (Triplet) tanβ= 4 tanβ= 4 tanβ= 40 tanβ= 40

The cross section for the EWIMP receives the sizable 1-loop correction, when the cross section is smaller than about 10-45cm2. The cross section for the EWIMP receives the sizable 1-loop correction, when the cross section is smaller than about 10-45cm2.

Indirect detection of EWIMP dark matter using γ-rays Indirect detection of EWIMP dark matter using γ-rays χ

• Sun

Annihilate

γ- ray

When , usual perturbation can not be applied due to the threshold singularity !! When , usual perturbation can not be applied due to the threshold singularity !!

W

m m >

χ

• π

W−

W+

γ γ

Halo

Calculation of annihilation cross sections is important!! Calculation of annihilation cross sections is important!!

Ladder diagram

Breakdown of perturbation in cal. of cross section Breakdown of perturbation in cal. of cross section

2

~ A α

2 2 2 2

~

W

m A m α

2

~

W

m A m α

χ

• χ
• Diagrams have an additional factor

for each weak gauge boson exchange.

2

/

W

m m α

+ +

• ● ●

+

Z W or Z W or Z We have to resum ladder diagrams!!

W+

W−

Intermediate states (EWIMP& partner) are almost on-shell. Threshold Singularity 1.Velocity of EWIMP:

• 2. Degeneracy between

EWIMP & partner

3

10 v c

−

• Bound states composed

by EWIMP & Partner’s pair appear if m > mW!! Bound states composed by EWIMP & Partner’s pair appear if m > mW!! Annihilation cross section is enhanced compared to leadings. Annihilation cross section is enhanced compared to leadings. Non-pertuvative effect We performed the resummation using NR-Lagrangian. We performed the resummation using NR-Lagrangian.

3 1

( sec ) v cm for W W σ χ χ

− + −

→

Leading order cal.

0.1( ) m GeV δ = 1( ) m GeV δ =

3

/ 10 v c

−

=

Annihilation cross section including effects of T.S. Annihilation cross section including effects of T.S.

Triplet Doulet

Constraint on MSSM parameters by gamma rays (1-10GeV) from the galactic center using EGRET observation . Constraint on MSSM parameters by gamma rays (1-10GeV) from the galactic center using EGRET observation . Models of particle physics can be constrained by the

• bservation !!

Models of particle physics can be constrained by the

• bservation !!

Gamma ray flux is increased For example

Gamma ray signal from EWIMP annihilation in galactic cneter Gamma ray signal from EWIMP annihilation in galactic cneter

2 14 2 1 27 3 1

( ) 1 9.3 10 ( ) 10

i i i

d E dN v TeV cm s J dE dE cm s m

γ γ

σ

− − − − −

Ψ ⎛ ⎞ < > ⎛ ⎞ = × ∑ ΔΩ ⎜ ⎟⎜ ⎟ ⎝ ⎠ ⎝ ⎠

2 3 . .

1 ( ) 8.5 ( ) 0.3

l o s

J d dl kpc GeV cm ρ θ

− ΔΩ

⎛ ⎞ = Ω ⎜ ⎟ ΔΩ ⎝ ⎠

∫ ∫

Flux strongly depends on dark matter profile, so evaluation of the profile is important !!

(NFW:α= 1) (Moore:α= 1.4) (King:α= 0)

( ) r ρ

( ) ( 0) r r r

α

ρ

−

• ∼

Cuspy structure Recent N-body Simulations suggest

Excluded region by EGRET from G.C. for different profiles

Indirect detection of EWIMP dark matter using positrons Indirect detection of EWIMP dark matter using positrons

Positron Fraction = (Positron Flux) / (Positron + Electron Flux) Background Large excess of the positron fraction !! Large excess of the positron fraction !!

Summary

When the mass of EWIMP is large , some 1-loop diagrams significantly contribute to the collision cross section (Non-decoupling). In cal. of the annihilation cross section, non-perturbative effects become important, and the cross section is enhanced (Threshold Singularity). We computed the cross sections of dark matter relevant to direct and indirect detections when the DM is non-singlet (EWIMP). We calculated the collision cross section between EWIMP and nucleus, gamma ray flux from the galactic center, positron excess in C.R..

(2)L SU

( )

W

m m >

If EWIMP is realized as the dark matter, strong signals are expected in both direct and indirect detections. In direct detections, EWIMP has the collision cross section larger than 10-46cm2 for the triplet, and 10-47cm2 for the doublet case. In indirect detections, strong signals such as excesses of gamma rays and positrons in C.R. are expected. Some regions in MSSM parameter space are already constrained by the EGRET observation.