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Overview of indirect dark matter detection. Jae Ho HEO Theoretical High Energy group jaeheo1@gmail.com Yonsei University . 2012 Jindo Workshop, Sep. 20-23. Outlines. Introduction Relic abundance Indirect detections (positrons, antiprotons, photons)
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Overview of indirect dark matter detection Jae Ho HEO Theoretical High Energy group jaeheo1@gmail.com Yonsei University 2012 Jindo Workshop, Sep. 20-23
Outlines Introduction Relic abundance Indirect detections (positrons, antiprotons, photons) Direct detections (annual modulation, iDM) Triplet dark matter (no hypercharge Y=0, but weak charge SU(2) ) Future work Heo, PRD 80, 033001 (2009)
Galactic Rotation Curves 1930s Zwicky L. Bergstrom Rept. Prog. Phys 63, 793 (2000) • Newtonian prediction expect velocity to fall across the galactic disk as mass density falls. • Observed rotational curves not consistent with visible distribution of matter. • Supports the view that galaxies are immersed in a halo of so-called dark matter. • Appears to make up ~83% of mass in the Universe
World Composition(mass-energy density) Nobody knows these
Dark Matter Annihilation Dark matter particles can annihilate and create other particles relic abundance, indirect DM detection Antimatters: rarely produced in astrophysical background. Gamma rays: can transport freely long distance without energy loss or transmutations of the direction.
RELIC ABUNDANCE Relic density : Time evolution Boltzmann equation WMAP Col. AJS 180, 330 (2009) WMAP data : 0.1097< WCDMh2<0.1165 (at 3s) Constant inverse freeze out temperature : xF~20-25 for 10 GeV<M <1000 GeV 25-… for M>1000 GeV Thermal average for this annihilation P. Gondolo NP B360, 124 (1991) v~0.3 c From Boltzman distribution considered relativity
Source for Cosmic Ray Signals • Emissivity/energy at location x from GC Injected particle spectra DM density at location x (DM halo profile) : NFW, Moore, core Isothermal, Einasto Boost factor Number of particles • Fluxes
Boost factors • Subhalo structure : • less than 10 or 20 at GH, • it can be very large ~100(000) around GC • Sommerfeld nonperturbative effect : non-relativistic velocity and a long-range • attractive force • For a singe Abelian massless vector with potential • Breit-Wigner resonance : In case that mediators have mass just below twice the DM • mass • annihilation rates can be enhanced Cirelli et al., NPB 800, 204 (2008) Sommerfeld enhancement factor:
Propagation of CRs Particles, emitted by whatever process, must reach the detector (Earth) travelling through a medium with structure (the galaxy): interstellar gas, magnetic field We have a standard diffusion model (Galprop) which assumes the galaxy is a flat cylinder with free scape at the boundaries Space diffusion Energy loss Convective wind Casse, Lemoine, Pelleetier, PRD 65, 023002 (2002) Scattering in IS (H, He atoms)
Two-Zone model 8.5 kpc L=3-20 kpc H, He h=0.1 kpc SUN R=20 kpc Positrons: Antiprotons: Three propagation models : MIN, MED, MAX Correspond to minimal(MIN), medium (MED), maximum(MAX) antiproton fluxes. Deliahaye et al., PRD 77, 063527 (2008)
A model with magnetic dipole Heo, Kim, arXiv:1207.1341
Positrons • Predicted signals have almost no difference in halo profiles or diffusion models. • Predicted fractions exhibit rather sharp distribution at E~M, since our candidate can directly annihilate into electron-positron pair. • Predicted signals with the boost factor, 30-80 nicely fit measurements of the PAMELA, Fermi LAT, etc • We predict that an enhancement of 16 factor comes from Sommerfeld effect, and the rest 2-5 enhancements from the subhalo structure (dark clumps). Solar modulation at low energies (<10 GeV) Gleeson et al., Astropart. Phys. 154, 1011 (1968)
Gamma-Rays from GH • Almost no difference in the halo profiles • Slightly touch EGRET anomaly The predicted signals are within the current unobservable experimental constraint.
Antiprotons • No difference in halo profiles • Sensitive to the propagation models • Viable in MIN propagation model • Likely rule out for other propagation • Models, MED and MAX • The MED propagation parameters are in • uncertainty of one order of magnitude. • The MED propagation model might be • viable, if we consider uncertainty of • Propagation parameters.
Gamma-Rays from around GC Most complex regions in galaxy due to many possible sources : difficult to model the diffuse emission, and discriminate the DM annihilation signals from background. Smoking-gun signatures : monochromatic gamma-ray lines
Signals from around GC • Predictions are under experimental exclusion limits Fermi. Col., astro-ph/1205.12739 C. Weniger, hep-ph/1205.2797 E. Tempel, A. Hektor, M. Raidal, hep-ph/1205.1045 A. Kounine, astro-ph/1009.5349; http://ams.cern.ch. • The predicted signals are in the potential probe at the AMS-02 with the better experimental method (energy resolution 1.5-2%, Fermi LAT 11-13%).
M=100 GeV M=50 GeV M=300 GeV
Triplet Dark Matter Heo, PRD 80, 033001 (2009) • Extend the SM with an exotic lepton triplet E per family • Anomaly constraints provide gauge charge of E Fermion gauge charges
There are no photon and Z boson couplings • : This avoids direct detection constraint. • Neutral and charged Es have mass splitting by radiative correction (~165 MeV) • :induce inelastic scattering for direct detection, but splitting is large -> also avoid direct detection constraint. • I need consider indirect detection of this model Jae Ho HEO
Future Work Thanks for the attention • Fermion triplet dark matter • Scalar triplet dark matter • Neutrino Telescopes : We need the magnetic profile of the SUN