viviana niro - taup conference · 2015. 8. 4. · bottino et al., hep-ph/0212379, hep-ph/0401186...

Light neutralinos and neutrino signal

Viviana Niro

Max Planck Institut fuer Kernphysik, Heidelberg

Roma, 1-5 July, 2009

in collaboration with A. Bottino and N. Fornengo(work in progress)

Viviana Niro (MPIK, Heidelberg) Light neutralinos and neutrino signal TAUP 2009 1 / 17

Outline

1 Direct detection and light neutralinosThe effective MSSMChanneling effect and WIMP DFHadronic uncertaintiesDAMA/LIBRA and light neutralinos

2 Indirect detection in neutrinosThe Super-Kamiokande detectorAnnihilation inside the Earth

3 Conclusions


Direct detection and light neutralinos The effective MSSM

The effective MSSM

Effective MSSM at the electroweak scale is defined by five independent parameters givenby

M1 = U(1) gaugino massM2 = SU(2) gaugino massµ = Higgs mixing mass parametertanβ = ratio of the two Higgs vevsmA = mass of the CP-odd neutral Higgs bosonmq̃ = squark soft mass common to all quarksml̃ = sleptons soft mass common to all sleptonsA = trilinear parameter for the third family (Ab̃ = At̃ ≡ A mq̃ , Aτ̃ ≡ A ml̃)

⇒ No gaugino-mass unification at the GUT scale is assumed

Bottino et al., hep-ph/0212379, hep-ph/0401186

⇒ lower limit on neutralino mass from upper bound on (ΩCDM h2):

(ΩCDM h2)max = 0.122 → mχ ≥ 7 GeV

Bottino et al., hep-ph/0304080


Direct detection and light neutralinos Channeling effect and WIMP DF

Channeling effect and WIMP DF

Channeling effect: ions can have an anomalous penetration into the lattice of the crystal(ions moving quasi-parallel to the crystallographic axes)⇒ energy losses mainly due to electronic contributions ( 6= quenching factor)⇒ different annual modulation allowed region in the (mχ, ξ σ) plane

Bernabei et al., 0710.0288 [astro-ph]


Direct detection and light neutralinos Channeling effect and WIMP DF

Channeling effect and WIMP DF

Channeling effect: ions can have an anomalous penetration into the lattice of the crystal(ions moving quasi-parallel to the crystallographic axes)⇒ energy losses mainly due to electronic contributions ( 6= quenching factor)⇒ different annual modulation allowed region in the (mχ, ξ σ) plane

Bernabei et al., 0710.0288 [astro-ph]

Wimp DF: different form of the WIMP density profile Belli et al., hep-ph/0203242

From the galactic rotational curve: 170 km sec−1 ≤ v0 ≤ 270 km sec−1

⇒ range of ρ0, from maximal amount of non-halo component in the Galaxy⇒ different annual modulation allowed region in the (mχ, ξ σ) plane

Examples:the cored-isothermal sphere

ρ(r) =v20

4πG

3R2c + r2

(R2c + r2)2, Rc = 5 kpc

the NFW profile

ρ(r) = ρ0

„

R0

r

«γ »1 + (R0/a)

α

1 + (r/a)α

–(β−γ)/α

, (α, β, γ, a) = (1, 3, 1, 20 kpc)


Direct detection and light neutralinos Hadronic uncertainties

Hadronic uncertainties

Hadronic uncertainties: coupling between the Higgs boson and the nucleon

Ih,H =X

q

kh,Hq mq〈N|q̄q|N〉 = k

h,Hu−type gu + k

h,Hd−type gd ,

introducing

σπN =1

2(mu + md)〈N|ūu + d̄d |N〉 , σ0 ≡

1

2(mu + md)〈N|ūu + d̄d − 2s̄s|N〉 ,

r = 2ms/(mu + md)

⇒ gu ≃427

(mN +198σπN −

12r(σπN − σ0)) , gd ≃

227

(mN +234

σπN +254r(σπN − σ0))


Direct detection and light neutralinos Hadronic uncertainties

Hadronic uncertainties

Hadronic uncertainties: coupling between the Higgs boson and the nucleon

Ih,H =X

q

kh,Hq mq〈N|q̄q|N〉 = k

h,Hu−type gu + k

h,Hd−type gd ,

introducing

σπN =1

2(mu + md)〈N|ūu + d̄d |N〉 , σ0 ≡

1

2(mu + md)〈N|ūu + d̄d − 2s̄s|N〉 ,

r = 2ms/(mu + md)

⇒ gu ≃427

(mN +198σπN −

12r(σπN − σ0)) , gd ≃

227

(mN +234

σπN +254r(σπN − σ0))

Experimental values:

41 MeV ≤ σπN ≤ 57 MeV R. Koch (1982) , 55 MeV ≤ σπN ≤ 73 MeV Pavan et al. (2001)

30 MeV ≤ σ0 ≤ 40 MeV Gasser and Leutwyler (1982)

Nuclear sets considered:

(r , σπN , σ0) = ((29, 45, 30); (25, 41, 40); (25, 57, 30); (25, 55, 40); (25, 73, 30))


Direct detection and light neutralinos DAMA/LIBRA and light neutralinos

DAMA/LIBRA and light neutralinos

DAMA/LIBRA results ⇒ annual modulation effect at a 8.2 σ C .L.(total exposure of 0.82 ton year) Bernabei et al., 0804.2738 [astro-ph], 0804.2741 [astro-ph]

The DAMA/LIBRA annual modulation region is compatible with neutralinos withmasses mχ ≤ 100 GeV (red: 0.098 ≤ Ωχh2 ≤ 0.122; blue: Ωχh2 ≤ 0.098) Bottino et al., 0806.4099 [hep-ph]


Indirect detection in neutrinos


Particles of Dark Matter gravitationally trapped inside celestial bodies ⇒ accumulate inthe central part of the body ⇒ annihilate producing neutrinosThe differential neutrino flux is:

dNν

dEν=

Γann4πd2

X

f

BRfdNf

dEν,

d = distance from the source; Γann = annihilation rate inside the celestial body

Γann =C

2tanh2(t0/τA) , τA ∝ (〈σann v〉)

−1/2

Production: Different annihilation channels

χχ → qq̄, τ τ̄ , ZZ , W +W−, gg , higgs channels

Propagation:inside the Sun → oscillation, neutral and charged current interactionsinside the Earth → mainly vacuum oscillation (we considered θ13 = 0)

Cirelli et al., hep-ph/0506298; Blennow et al., 0709.3898 [hep-ph]




Detection: Neutrino-Muon conversion in the rock below the detector

The flux of neutrino induced muons with energy Eµ and zenith angle θz is given by:

dNµ

dEµd cos θz= NA

Z mχ

Eµ

dEν

Z ∞

0

dX

Z Eν

Eµ

dE′µ g(Eµ, E

′µ;X ) S(Eν , E

′µ)

g(Eµ, E′µ;X ) =

δ(X − X0)

a + bEµ, X0 =

1

bln

a + bE ′µa + bEµ

a, b = parameters for energy loss (from Bethe-Block formula)

S(Eν , E′µ) =

dNν

dEνd cos θz

dσν(Eν , E′µ)

dE ′µ

Gaisser and Stanev, Phys.Rev.D30: 985, 1984

with dNνdEνd cos θ

= ν flux at detector (after oscillation, NC and CC interactions)


Indirect detection in neutrinos The Super-Kamiokande detector

The Super-Kamiokande detector

Φµ(θz)S,T =1

A(Lmin, θz )

Z mχ

Eµ(Lmin)

dEµdNµ

dEµd cos θzAS,T (Eµ, θz )

Lipari and Lusignoli, hep-ph/9803440

AS,T (Eµ, θz ) = effective areas for stopping and through-going muons trajectoriesFor the Super-Kamiokande detector: Lmin = 7 m (Eµ,min = 1.6 GeV)

-1.0 -0.8 -0.6 -0.4 -0.2 0.0800

900

1000

1100

1200

1300

1400

cos ΘZ

Eff

ecti

veA

rea@m

2D

SK limit on muons flux:

Φµ(90% C .L.) =N90

A × T

N90= the upper Poissonian limit(90% C .L.) given the number of measuredevents and expected background

Desai et al., hep-ex/0404025 ; Ashie et al., hep-ex/0501064


Indirect detection in neutrinos The Super-Kamiokande detector

Atmospheric neutrinos

Zenith angle distribution for stopping and through-going muons.red lines: νµ ↔ ντ oscillation with sin

2 θ = 0.50 and ∆m2 = 2.40 10−3 eV2best-fit values from Schwetz et al., 0808.2016 [hep-ph]

STOPPING MUONS THROUGH-GOING MUONS

-1.0 -0.8 -0.6 -0.4 -0.2 0.00.0

0.2

0.4

0.6

0.8

1.0

1.2

cos ΘZ

FΜ@1

0-13

cm-

2s-

1sr-

1D

Super-K 2001 HStat. err. only - 90% CLL

-1.0 -0.8 -0.6 -0.4 -0.2 0.00.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

cos ΘZ

FΜ@1

0-13

cm-

2s-

1sr-

1D

Super-K 2001 HStat. err. only - 90% CLL


Indirect detection in neutrinos Annihilation inside the Earth

Annihilation inside the Earth

Upward stopping and through-going muons due to neutralino annihilation inside theEarth, for different nuclear sets

work in progress (preliminary plot)


Conclusions

Conclusions

We have calculated the neutrino signal in through-going and stoppingmuons for the case of neutralino annihilation inside the Earth, for aSK-like detector

We have included the hadronic uncertainties and the neutralinoconfiguration compatible with the DAMA/LIBRA experimet,considering the channeling effect and the different WIMP distributionfunctions

We have shown how the stopping muons represent a powerful sourceto test the neutralino light mass region

Outlook: the study of the induced muon flux from the Sun


BACK-UP SLIDES

Range of the MSSM parameters:

1 ≤ tanβ ≤ 50100 GeV ≤ |µ| ≤ 1000 GeV5 GeV ≤ M1 ≤ 500 GeV100 GeV ≤ M2 ≤ 1000 GeV100 GeV ≤ mq̃ , ml̃ ≤ 3000 GeV90 GeV ≤ mA ≤ 1000 GeV-3 ≤ A ≤ 3

Experimental constraints imposed:

1) accelerator data on supersymmetric and Higgs boson searches2) measurements of the b → s + γ:2.89 ≤ BR(b → s + γ) 10−4 ≤ 4.213) upper bound on the branching ratio BR(B0s → µ

− + µ+):BR(B0s → µ

− + µ+) < 1.2 10−7

4) measurements of the muon anomalous magnetic moment aµ ≡ (gµ − 2)/2:

-98 ≤ ∆aµ 1011 ≤ 565


Direct detection and light neutralinosThe effective MSSMChanneling effect and WIMP DFHadronic uncertaintiesDAMA/LIBRA and light neutralinos

Indirect detection in neutrinosThe Super-Kamiokande detectorAnnihilation inside the Earth

Conclusions

viviana niro - taup conference · 2015. 8. 4. · bottino et al., hep-ph/0212379, hep-ph/0401186...

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