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This document discusses various strategies in the search for dark matter, specifically focusing on weakly interacting massive particles (WIMPs). Key methodologies include direct detection through nuclear recoil measurement and indirect detection involving neutrinos, antiprotons, positrons, and gamma rays. The document reviews current limits on WIMP searches, presents results from experiments like DAMA, and explores neutron capture and annihilation processes relevant to dark matter interactions. Insights into neutrino flux from the Earth and Sun, as well as implications of detection experiments like IceCube, are included.
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Search for Dark Matter physics 805 fall 2008
WIMP search strategies • Direct detection • Indirect detection:– neutrinos from the Earth/Sun– antiprotons from the galactic halo– positrons from the galactic halo– gamma rays from the galactic halo– gamma rays from external galaxies/halos– synchrotron radiation from the galactic center / galaxy clusters– ...
WIMP + nucleus WIMP + nucleus • Measure the nuclear recoil energy • Suppress backgrounds • Search for an annual modulation due to the Earth’s motion around the Sun direct detection - general principles c c c c c December June
c WIMP Capture and Annihilation n nm DETECTOR c + c W + W n + n
Inner Core Detector Inner Core (same region as AMANDA) 7 IceCube + 18 AMANDA strings 225 DOMs + 540 OMs
rc velocity distribution c n interactions sscatt n int. m int. nm Gcapture Gannihilation m neutralino capture and annihilation sun Freese, ’86; Krauss, Srednicki &Wilczek, ’86 Gaisser, Steigman & Tilav, ’86 Silk, Olive and Srednicki, ’85Gaisser, Steigman & Tilav, ’86
indirect detection for cyclists e.g.104 m2n-telescope searches for 500 GeV WIMP 300 km/s > LHC limit 1. - flux 2. solar cross section
Nsun = capture rate = annihilation rate _ c c WW 250 GeV 500 GeV mnm 3. Capture rate by the sun 4. Number of muon-neutrinos 0.1is the leptonic branching ratio
5.5 x 1023 cm-3 104 m2 ~ _ # events = 10 per year
AMANDA 180d SK Antares 3 years 1km3 (IceCube) PRELIMINARY WIMP search Limits on muon flux from Earth Limits on muon flux from Sun Disfavored by direct search (CDMS II)
IceCube vs Direct Detection (Zeppelin4/Genius) Black: out Green: yes Blue: no