Indirect Dark Matter Search with AMS

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Indirect Dark Matter Search with AMS
Cosmic Ray Astrophysics with AMS02 PS1 D.Haas
T. Siedenburg for the AMS
Collaboration
6emes Rencontres du Vietnam, Hanoi
9-Aug-2006
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Cosmic Puzzle
Clues in CR Spectra ?
Precision Cosmology WMAP CMB Power SpectrumSDSS
3D Matter SpectrumHubble SN-Ia Redshift
1/s/GeV
1/d/GeV
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Detecting a SUSY Neutralino as Dark-Matter
Candidate
WIMP Weakly Interacting Massive Particle
Structure Cold Dark-Matter
Direct Detection current local density SD/SI
Visible Matter
Dark Matter Halo
Indirect Detection Neutralino-Annihilation
Solar/terrestrial neutrinos
GC
solar lifetime average
g
AMS02 Dark-Matter Detection
Spectrum/Line from GC
Charged Anti-Particles 1GeV-1TeV 5 kpc Sphere
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Dark Matter Detection Requirements
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AMS01 Precursor Flight
Permanent Magnet 0.15 Tm26 Si-Strip Tracker
Planes4 Sc-Panel TOF Trigger LayersAerogel
Cerenkov Veto ACC 108 Events in 10 days
AMS01
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AMS01 Positron Selection above 3.5 GeV

• 3 track events with converted g middle
  track from primary e
• Efficient track reconstruction
• Reject high dE/dX Qgt1 events
• Keep backtraced extraterrestrial events
• Background e with wrong charge p ? p p
  p p ? p p0 ? p ee (g)
• Reconstruct invariant masses at radiation and
  conversion vertex

Primary Positron
TOF 1
Photon
TOF 2
_at_
_at_
TOF 3
TOF 4
SecondaryPositron
SecondaryElectron
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Selected AMS01 Positrons
Proton MC
Background from p and e MCReweight for
geomagnetic cutoff spectral indexScale
to measured p and e flux
Geomagnetic Cutoff
118 Selected 24.9 Protons 6.5
Electrons
Spectral Index
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Acceptance and Livetime Corrections for Flux
Calculation
dF / dE N / (A T DE)
For each 4sec Flight Period Get Shuttle
Coordinates Backtrace particle in 9
cosq, 8 j, 8 p bins Sum DAQ livetime
for extraterrestrial tracksSeparately up/down
e/e 5000 CPU Days
Upward Shuttle Floor
Trapped Particle
Geometrical Acceptance A
Average Livetime T
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AMS01 Lepton Fluxes
AMS01 Positron Fraction
J.Olzem, H.Gast
J.Olzem, H.Gast
Cancellation of systematics in fraction(
Detector acceptance / Livetime )
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Improve with AMS02
Tracking and Particle ID
3m 6700 kg
TRD Xe/CO2 Straws prej. gt102 1-300 GeV
0.5m2sr
3.5m
TOF Trigger (2up2low) st 120ps b dE/dX Z
Superconducting Magnet 0.8 Tm2 2.5t
superfluid He
Silicon Strip Tracker 6m2 p up to 1TV and
Z(dE/dX)
RICH Aerogel/NaF 3s Sep. A26 1-12 GeV Z
ECAL 3D lead/scint-fibre h rej. gt103 1-300 GeV
0.05m2sr
3 years above atmosphere
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Charge / Isotope Separation
TRD Positron Proton Separation
dE/dX from TrackerRICH (and TOF)
A/Z 2 GSI Beamtest
1 Layer
0
20 Layer TRD Beamtest
b from RICH (1-12 GeV/n)
Momentum from Trackerwith Supercond. Magnet?
Mass for Isotope Sep.
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ECAL 16.4 X0 18 x/y samplings
AMS02 GAMMA DETECTION
Effective Area / cm2
Energy and angle 1 GeV 1 TeV h/e Separation
103 shower-shape Acceptance 0.05m2sr
E / GeV
Angular Resolution / deg
Energy Resolution /
Star Tracker 30
E / GeV
E / GeV
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AMS02 Nuclei and Isotopes
Determine Propagation Model Parameter Errors from
Variation with AMS02 MC Error Estimation
Secondary/Primary Traversered
MatterUnstable/Stable Confinement Time
105 C 104 B gt 100 GeV/n in 3 years
105 10Be 0.5-10 GeV in 3 years
B/C
10Be / 9Be
Agl
NaF
AMS02 MC
TOF
E / GeV/n
E / GeV/n
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4x106 AMS02 Positrons from 5-300 GeV
Proton Rejection 106 from TRD
1000-100 ECAL 100-1000 E/p
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Improve precision of SM background predictionto
enhance sensitivityfor subtle deviations within
the same dataset e.g. WIMP annihilations
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Test of mSUGRA parameter space with precise
positron fraction
Focus Point
Rapid Funnels
Constraints gm-2 mh WCDM
b?sg
BS?mmmt175.2GeV mb4.2GeV as0.1187 Fixed
A0 0 sign(m) 1 Free m0 m1/2
tanb
E / GeV
E / GeV
BF 6.1e3
BF 1.7e5
Bulk Point
Co-Annihilation
BF 1.2e5
BF 3.2e3
E / GeV
E / GeV
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AMS02 Antiprotons and Gammas
Electron Rejection 104 from TRD ECAL E/p
1 GeV EGRET Excess and de Boer DM ring
interpretation hard to confirmCuspier
Halo-Profile flux x10
106 Antiprotons 0.5-100 GeV
Sensitivity 7x10-9 / cm2 / s
Antiprotons sensitive to solar modulation
Ro 8.0 kpc, r0 0.3 GeV/cm3, a 20 kpc
p
LIS Geomagn.cutoff
A.Jacholskowska et al.Phys.Rev.D 74 023518 (2006)
from galactic center
m0 60 GeVm1/2 250 GeVA00 tanb10
mgt0
BF 2.0e1
(3 years)
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Conclusion AMS Dark-Matter Detection
AMS01 Successful flight, HEAT Positron excess
not excluded
AMS02 Complete, large acceptance, 3 years above
atmosphere
Tracking 3 TV RICH 1
12 GeV Calorimetry 1 GeV 1 TeV TRD 1 300
GeV
High statistics e, p and AZ to tune cosmic models
e, p, and g spectra for combined dark-matter fit
AMS02 is on schedule for flight in 2009
Shuttle isback to flight