Searches for Dark Matter Annihilations in the Sun and Earth with - - PowerPoint PPT Presentation

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Searches for Dark Matter Annihilations in the Sun and Earth with - - PowerPoint PPT Presentation

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Searches for Dark Matter Annihilations in the Sun and Earth with IceCube and DeepCore Matthias Danninger for the IceCube collaboration Content Overview: IceCube (see IceCube status plenary talk by D. Williams ) DeepCore key facts

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Searches for Dark Matter Annihilations in the Sun and Earth with IceCube and DeepCore

Matthias Danninger for the IceCube collaboration

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 2

Content

Overview:

  • IceCube (see IceCube status plenary talk by D. Williams )
  • DeepCore

key facts →

Dark Matter searches:

  • Earth

work in progress, no new results → → neutrinos from Dark Matter

  • Sun

considered WIMP models → → analysis strategy & current limits

Looking forward: (IceCube&DeepCore prospects) Conclusions

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 3

Deep Core

  • 6 additional strings – 60 High

Quantum Efficiency PMTs (deployed in deep ice)

  • 7m DOM spacing (17m standard),

72m inter-string spacing. → focus energies (few GeV~1TeV)

  • 4π detector using IceCube as an

active veto. Southern sky sources (GC) and year round observation for the Sun.

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 4

Neutrinos from Dark Matter (Sun)

physics uncertainties involved:

  • relic density calculations
  • DM distribution in the halo

→ smaller effect for this method

→ mean density ρ l o

c a l = 0.3 GeV/c2 cm3

  • velocity distribution
  • WIMP properties (MSSM/UED...)
  • interaction of WIMPs with matter (capture)

→ planetary effects (high masses) → Sun composition

  • self interaction (annihilation)

signature: ν excess over background from Sun direction

background: atm µ ~O(109) events/year (downwards) atm ν ~O(103) events/year (all directions)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 5

Investigated DM candidates

  • arise in extensions of the Standard Model
  • assumed to be stable: relics from the Big Bang
  • mass from few GeV to few TeV

candidates:

  • MSSM: lightest super-symmetric particle (LSP)

neutralino, χ0

1 = z1 1 B + z1 2 W3 + z1 3 H0 1+ z1 4 H0 2 simulation of “softest” and “hardest” case

hard: m(χ0

1) [35 GeV – 5 TeV] (τ+τ− / W+W-)

soft: m(χ0

1) [35 GeV – 5 TeV] (b b)

  • Universal extra dimensions: Lightest Kaluza-

Klein particle (LKP), B( 1

) or γ ( 1 )

fixed branching ratios: m(γ( 1

) [250 GeV–3TeV]

R

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 6

Low Energy neutrino Search

ν-energies of ~ 1 TeV have high interaction probability in Sun → Sun becomes ν-opaque → low mean muon energy in detector short tracks with few hits →

ν-interaction in the Sun Signal MC

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 7

Analysis strategy

E x p e r i m e n t a l l y

  • b

t a i n e d q u a n t i t y

Remove atmospheric muon events until data sample is dominated by atmospheric neutrino events

ΓA Cc ~ σS

D

Φµ

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 8

Analysis strategy

E x p e r i m e n t a l l y

  • b

t a i n e d q u a n t i t y

Remove atmospheric muon events until data sample is dominated by atmospheric neutrino events

ΓA Cc ~ σS

D

Φµ

Mostly neutrino events in final data sample

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 9

Analysis strategy

E x p e r i m e n t a l l y

  • b

t a i n e d q u a n t i t y

Remove atmospheric muon events until data sample is dominated by atmospheric neutrino events

ΓA Cc ~ σS

D

Φµ

SVM output value from signal simulations, data and three background components

Abbasi et al., Phys. Rev. Lett. 102, 201302 (2009)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 10

Analysis strategy

E x p e r i m e n t a l l y

  • b

t a i n e d q u a n t i t y

Remove atmospheric muon events until data sample is dominated by atmospheric neutrino events

ΓA Cc ~ σS

D

Φµ

Events close to the direction of the Sun

Abbasi et al., Phys. Rev. Lett. 102, 201302 (2009)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 11

Abbasi et al., Phys. Rev. Lett. 102, 201302 (2009) (IC22 result)

IceCube-22 & study: Only used data, when Sun is below the horizon main syst. uncertainty: Photon propagation in the ice & absolute DOM efficiency (~20%) relate muon flux and WIMP-nucleon cross- section:

Results: Neutralino DM (LSP)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 12

Results: Neutralino DM (LSP)

IceCube-22 & study: Only used data, when Sun is below the horizon main syst. uncertainty: Photon propagation in the ice & absolute DOM efficiency (~20%) relate muon flux and WIMP-nucleon cross- section:

Abbasi et al., Phys. Rev. Lett. 102, 201302 (2009) (IC22 result)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 13

Abbasi et al., Physical Review D81 (2010) 057101. (IC22 result)

IceCube-22 & study: Only used data, when Sun is below the horizon main syst. uncertainty: Photon propagation in the ice & absolute DOM efficiency (~20%) relate muon flux and WIMP-nucleon cross- section:

<E

νμ > = 53 GeV

Results: Kaluza-Klein DM (LKP)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 14

Results: Kaluza-Klein DM (LKP)

IceCube-22 & study: Only used data, when Sun is below the horizon main syst. uncertainty: Photon propagation in the ice & absolute DOM efficiency (~20%) relate muon flux and WIMP-nucleon cross- section:

Abbasi et al., Physical Review D81 (2010) 057101. (IC22 result)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 15

Prospects: Neutralino DM (LSP)

IceCube-22 & study: Only used data, when Sun is below the horizon main syst. uncertainty: Photon propagation in the ice & absolute DOM efficiency (~20%) relate muon flux and WIMP-nucleon cross- section:

Abbasi et al., Phys. Rev. Lett. 102, 201302 (2009) (IC22 result)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 16

IceCube-22 & study: Only used data, when Sun is below the horizon main syst. uncertainty: Photon propagation in the ice & absolute DOM efficiency (~20%) relate muon flux and WIMP-nucleon cross- section:

I C 8

  • n

l y IC80+DC6 Abbasi et al., Phys. Rev. Lett. 102, 201302 (2009) (IC22 result)

Prospects: Neutralino DM (LSP)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 17

IceCube-22 & study: Only used data, when Sun is below the horizon main syst. uncertainty: Photon propagation in the ice & absolute DOM efficiency (~20%) relate muon flux and WIMP-nucleon cross- section:

I C 8

  • n

l y IC80+DC6 Additional mass 35GeV Abbasi et al., Phys. Rev. Lett. 102, 201302 (2009) (IC22 result)

Prospects: Neutralino DM (LSP)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 18

effective area for final event selection as function of Eν in the range 50-1000 GeV, for

νµ and anti-νµ from the

direction of the Sun. The result is an average

  • ver the austral winter.

IC22: Systematic effects are in-cluded at the 1 level, σ and statistical uncertainty of the same level are shown with error bars.

Abbasi et al., Physical Review D81 (2010) 057101. (IC22 result) With DC down to ~20GeV

Prospects:WIMP-Model-independent Result

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 19

Conclusion

AMANDA-II analysis are finishing (full 6y-data result soon) First IceCube results are published

→ IC22 results for searches from Sun & Halo → IC40 & IC59 analysis ongoing → IC79 incl. DeepCore is taking data

DeepCore makes low-energy region 10 ~ 100 GeV accessible for IceCube Looking forward:

Including isolated hits and new reconstruction techniques All year search for low WIMP masses (IceCube active veto for DeepCore) String 79 & 80 will create even denser DeepCore array

DeepCore layout (top view)

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Matthias Danninger July 22, 2010 TeVPA Particle Astrophysics 2010 20

Conclusion

AMANDA-II analysis are finishing (full 6y-data result soon) First IceCube results are published

→ IC22 results for searches from Sun & Halo → IC40 & IC59 analysis ongoing → IC79 incl. DeepCore is taking data

DeepCore makes low-energy region 10 ~ 100 GeV accessible for IceCube Looking forward:

Including isolated hits and new reconstruction techniques All year search for low WIMP masses (IceCube active veto for DeepCore) String 79 & 80 will create even denser DeepCore array

79 & 80

DeepCore layout (top view)